From ade887e43a2dfc5d4257cb2e2d7cb3c0be25fc26 Mon Sep 17 00:00:00 2001
From: Tong Mu <dkwingsmt@gmail.com>
Date: Wed, 22 Dec 2021 00:22:17 -0800
Subject: [PATCH 1/3] Impl

---
 .../windows/flutter_window_win32_unittests.cc | 43 ++++-----
 .../platform/windows/flutter_windows_view.cc  | 89 +++++++++----------
 shell/platform/windows/flutter_windows_view.h | 31 ++++---
 .../platform/windows/keyboard_handler_base.h  | 29 ------
 .../platform/windows/keyboard_key_handler.cc  | 19 ----
 shell/platform/windows/keyboard_key_handler.h | 15 ----
 .../windows/keyboard_win32_unittests.cc       |  4 +-
 shell/platform/windows/text_input_plugin.cc   |  5 +-
 shell/platform/windows/text_input_plugin.h    | 22 ++---
 9 files changed, 87 insertions(+), 170 deletions(-)

diff --git a/shell/platform/windows/flutter_window_win32_unittests.cc b/shell/platform/windows/flutter_window_win32_unittests.cc
index 1b4a77f13649a..0968ac0a2f51a 100644
--- a/shell/platform/windows/flutter_window_win32_unittests.cc
+++ b/shell/platform/windows/flutter_window_win32_unittests.cc
@@ -35,17 +35,14 @@ static constexpr int32_t kDefaultPointerDeviceId = 0;
 class SpyKeyboardKeyHandler : public KeyboardHandlerBase {
  public:
   SpyKeyboardKeyHandler(flutter::BinaryMessenger* messenger,
-                        KeyboardKeyHandler::EventDispatcher redispatch_event) {
+                        KeyboardKeyHandler::EventDispatcher dispatch_event) {
     real_implementation_ =
-        std::make_unique<KeyboardKeyHandler>(redispatch_event);
+        std::make_unique<KeyboardKeyHandler>(dispatch_event);
     real_implementation_->AddDelegate(
         std::make_unique<KeyboardKeyChannelHandler>(messenger));
     ON_CALL(*this, KeyboardHook(_, _, _, _, _, _))
         .WillByDefault(Invoke(real_implementation_.get(),
                               &KeyboardKeyHandler::KeyboardHook));
-    ON_CALL(*this, TextHook(_))
-        .WillByDefault(
-            Invoke(real_implementation_.get(), &KeyboardKeyHandler::TextHook));
   }
 
   MOCK_METHOD6(KeyboardHook,
@@ -55,7 +52,6 @@ class SpyKeyboardKeyHandler : public KeyboardHandlerBase {
                     char32_t character,
                     bool extended,
                     bool was_down));
-  MOCK_METHOD1(TextHook, void(const std::u16string& text));
   MOCK_METHOD0(ComposeBeginHook, void());
   MOCK_METHOD0(ComposeCommitHook, void());
   MOCK_METHOD0(ComposeEndHook, void());
@@ -68,10 +64,11 @@ class SpyKeyboardKeyHandler : public KeyboardHandlerBase {
 
 // A text input plugin that can be spied on while it forwards calls to the real
 // text input plugin.
-class SpyTextInputPlugin : public KeyboardHandlerBase,
+class SpyTextInputPlugin : public TextInputPlugin,
                            public TextInputPluginDelegate {
  public:
-  SpyTextInputPlugin(flutter::BinaryMessenger* messenger) {
+  SpyTextInputPlugin(flutter::BinaryMessenger* messenger)
+      : TextInputPlugin(messenger, this) {
     real_implementation_ = std::make_unique<TextInputPlugin>(messenger, this);
     ON_CALL(*this, KeyboardHook(_, _, _, _, _, _))
         .WillByDefault(
@@ -82,7 +79,7 @@ class SpyTextInputPlugin : public KeyboardHandlerBase,
   }
 
   MOCK_METHOD6(KeyboardHook,
-               bool(int key,
+               void(int key,
                     int scancode,
                     int action,
                     char32_t character,
@@ -246,21 +243,24 @@ class TestFlutterWindowsView : public FlutterWindowsView {
   }
 
  protected:
-  void RegisterKeyboardHandlers(
+  std::unique_ptr<KeyboardHandlerBase> CreateKeyboardKeyHandler(
       flutter::BinaryMessenger* messenger,
       flutter::KeyboardKeyHandler::EventDispatcher dispatch_event,
       flutter::KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state)
       override {
-    auto spy_key_event_handler = std::make_unique<SpyKeyboardKeyHandler>(
+    auto spy_key_event_handler = new SpyKeyboardKeyHandler(
         messenger, [this](UINT cInputs, LPINPUT pInputs, int cbSize) -> UINT {
           return this->SendInput(cInputs, pInputs, cbSize);
         });
-    auto spy_text_input_plugin =
-        std::make_unique<SpyTextInputPlugin>(messenger);
-    key_event_handler = spy_key_event_handler.get();
-    text_input_plugin = spy_text_input_plugin.get();
-    AddKeyboardHandler(std::move(spy_key_event_handler));
-    AddKeyboardHandler(std::move(spy_text_input_plugin));
+    key_event_handler = spy_key_event_handler;
+    return std::unique_ptr<KeyboardHandlerBase>(spy_key_event_handler);
+  }
+
+  std::unique_ptr<TextInputPlugin> CreateTextInputPlugin(
+      flutter::BinaryMessenger* messenger) override {
+    auto spy_key_event_handler = new SpyTextInputPlugin(messenger);
+    text_input_plugin = spy_key_event_handler;
+    return std::unique_ptr<TextInputPlugin>(spy_key_event_handler);
   }
 
  private:
@@ -357,7 +357,6 @@ TEST(FlutterWindowWin32Test, NonPrintableKeyDownPropagation) {
                 KeyboardHook(_, _, _, _, _, _))
         .Times(1)
         .RetiresOnSaturation();
-    EXPECT_CALL(*flutter_windows_view.key_event_handler, TextHook(_)).Times(0);
     EXPECT_CALL(*flutter_windows_view.text_input_plugin, TextHook(_)).Times(0);
     win32window.InjectMessages(1,
                                Win32Message{WM_KEYDOWN, virtual_key, lparam});
@@ -410,7 +409,6 @@ TEST(FlutterWindowWin32Test, SystemKeyDownPropagation) {
                 KeyboardHook(_, _, _, _, _, _))
         .Times(1)
         .RetiresOnSaturation();
-    EXPECT_CALL(*flutter_windows_view.key_event_handler, TextHook(_)).Times(0);
     EXPECT_CALL(*flutter_windows_view.text_input_plugin, TextHook(_)).Times(0);
     win32window.InjectMessages(
         1, Win32Message{WM_SYSKEYDOWN, virtual_key, lparam, kWmResultDefault});
@@ -436,7 +434,7 @@ TEST(FlutterWindowWin32Test, SystemKeyDownPropagation) {
 // differ from non-printable characters in that they follow a different code
 // path in the WndProc (HandleMessage), producing a follow-on WM_CHAR event.
 TEST(FlutterWindowWin32Test, CharKeyDownPropagation) {
-  // ::testing::InSequence in_sequence;
+  ::testing::InSequence in_sequence;
 
   constexpr WPARAM virtual_key = 65;  // The "A" key, which produces a character
   constexpr WPARAM scan_code = 30;
@@ -463,9 +461,6 @@ TEST(FlutterWindowWin32Test, CharKeyDownPropagation) {
                 KeyboardHook(_, _, _, _, _, _))
         .Times(1)
         .RetiresOnSaturation();
-    EXPECT_CALL(*flutter_windows_view.key_event_handler, TextHook(_))
-        .Times(1)
-        .RetiresOnSaturation();
     EXPECT_CALL(*flutter_windows_view.text_input_plugin, TextHook(_))
         .Times(1)
         .RetiresOnSaturation();
@@ -485,7 +480,6 @@ TEST(FlutterWindowWin32Test, CharKeyDownPropagation) {
     EXPECT_CALL(*flutter_windows_view.text_input_plugin,
                 KeyboardHook(_, _, _, _, _, _))
         .Times(0);
-    EXPECT_CALL(*flutter_windows_view.key_event_handler, TextHook(_)).Times(0);
     EXPECT_CALL(*flutter_windows_view.text_input_plugin, TextHook(_)).Times(0);
     win32window.InjectMessages(2, Win32Message{WM_KEYDOWN, virtual_key, lparam},
                                Win32Message{WM_CHAR, virtual_key, lparam});
@@ -521,7 +515,6 @@ TEST(FlutterWindowWin32Test, ModifierKeyDownPropagation) {
                 KeyboardHook(_, _, _, _, _, _))
         .Times(1)
         .RetiresOnSaturation();
-    EXPECT_CALL(*flutter_windows_view.key_event_handler, TextHook(_)).Times(0);
     EXPECT_CALL(*flutter_windows_view.text_input_plugin, TextHook(_)).Times(0);
     EXPECT_EQ(win32window.InjectWindowMessage(WM_KEYDOWN, virtual_key, lparam),
               0);
diff --git a/shell/platform/windows/flutter_windows_view.cc b/shell/platform/windows/flutter_windows_view.cc
index 6aeb948a88e06..ee60f12676894 100644
--- a/shell/platform/windows/flutter_windows_view.cc
+++ b/shell/platform/windows/flutter_windows_view.cc
@@ -52,13 +52,13 @@ void FlutterWindowsView::SetEngine(
   engine_->SetView(this);
 
   internal_plugin_registrar_ =
-      std::make_unique<flutter::PluginRegistrar>(engine_->GetRegistrar());
+      std::make_unique<PluginRegistrar>(engine_->GetRegistrar());
 
   // Set up the system channel handlers.
   auto internal_plugin_messenger = internal_plugin_registrar_->messenger();
   InitializeKeyboard();
   platform_handler_ = PlatformHandler::Create(internal_plugin_messenger, this);
-  cursor_handler_ = std::make_unique<flutter::CursorHandler>(
+  cursor_handler_ = std::make_unique<CursorHandler>(
       internal_plugin_messenger, binding_handler_.get());
 
   PhysicalWindowBounds bounds = binding_handler_->GetPhysicalWindowBounds();
@@ -67,10 +67,11 @@ void FlutterWindowsView::SetEngine(
                     binding_handler_->GetDpiScale());
 }
 
-void FlutterWindowsView::RegisterKeyboardHandlers(
-    flutter::BinaryMessenger* messenger,
-    flutter::KeyboardKeyHandler::EventDispatcher dispatch_event,
-    flutter::KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state) {
+std::unique_ptr<KeyboardHandlerBase>
+FlutterWindowsView::CreateKeyboardKeyHandler(
+    BinaryMessenger* messenger,
+    KeyboardKeyHandler::EventDispatcher dispatch_event,
+    KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state) {
   // There must be only one handler that receives |SendInput|, i.e. only one
   // handler that might redispatch events. (See the documentation of
   // |KeyboardKeyHandler| to learn about redispatching.)
@@ -79,24 +80,22 @@ void FlutterWindowsView::RegisterKeyboardHandlers(
   // of the event. In order to allow the same real event in the future, the
   // handler is "toggled" when events pass through, therefore the redispatching
   // algorithm does not allow more than 1 handler that takes |SendInput|.
-  auto key_handler =
-      std::make_unique<flutter::KeyboardKeyHandler>(dispatch_event);
-  key_handler->AddDelegate(std::make_unique<KeyboardKeyEmbedderHandler>(
-      [this](const FlutterKeyEvent& event, FlutterKeyEventCallback callback,
-             void* user_data) {
-        return engine_->SendKeyEvent(event, callback, user_data);
-      },
-      get_key_state));
-  key_handler->AddDelegate(
+  auto keyboard_key_handler = std::make_unique<KeyboardKeyHandler>(dispatch_event);
+  keyboard_key_handler->AddDelegate(
+      std::make_unique<KeyboardKeyEmbedderHandler>(
+          [this](const FlutterKeyEvent& event, FlutterKeyEventCallback callback,
+                 void* user_data) {
+            return engine_->SendKeyEvent(event, callback, user_data);
+          },
+          get_key_state));
+  keyboard_key_handler->AddDelegate(
       std::make_unique<KeyboardKeyChannelHandler>(messenger));
-  AddKeyboardHandler(std::move(key_handler));
-  AddKeyboardHandler(
-      std::make_unique<flutter::TextInputPlugin>(messenger, this));
+  return keyboard_key_handler;
 }
 
-void FlutterWindowsView::AddKeyboardHandler(
-    std::unique_ptr<flutter::KeyboardHandlerBase> handler) {
-  keyboard_handlers_.push_back(std::move(handler));
+std::unique_ptr<TextInputPlugin> FlutterWindowsView::CreateTextInputPlugin(
+    BinaryMessenger* messenger) {
+  return std::make_unique<TextInputPlugin>(messenger, this);
 }
 
 uint32_t FlutterWindowsView::GetFrameBufferId(size_t width, size_t height) {
@@ -129,7 +128,6 @@ void FlutterWindowsView::ForceRedraw() {
 }
 
 void FlutterWindowsView::OnPreEngineRestart() {
-  keyboard_handlers_.clear();
   InitializeKeyboard();
 }
 
@@ -268,16 +266,18 @@ void FlutterWindowsView::OnResetImeComposing() {
 void FlutterWindowsView::InitializeKeyboard() {
   auto internal_plugin_messenger = internal_plugin_registrar_->messenger();
 #ifdef WINUWP
-  flutter::KeyboardKeyHandler::EventDispatcher dispatch_event = nullptr;
-  flutter::KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state =
+  KeyboardKeyHandler::EventDispatcher dispatch_event = nullptr;
+  KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state =
       nullptr;
 #else
-  flutter::KeyboardKeyHandler::EventDispatcher dispatch_event = SendInput;
-  flutter::KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state =
+  KeyboardKeyHandler::EventDispatcher dispatch_event = SendInput;
+  KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state =
       GetKeyState;
 #endif
-  RegisterKeyboardHandlers(internal_plugin_messenger, dispatch_event,
-                           get_key_state);
+  keyboard_key_handler_ = std::move(CreateKeyboardKeyHandler(
+      internal_plugin_messenger, dispatch_event, get_key_state));
+  text_input_plugin_ =
+      std::move(CreateTextInputPlugin(internal_plugin_messenger));
 }
 
 // Sends new size  information to FlutterEngine.
@@ -381,9 +381,7 @@ void FlutterWindowsView::SendPointerLeave(PointerState* state) {
 }
 
 void FlutterWindowsView::SendText(const std::u16string& text) {
-  for (const auto& handler : keyboard_handlers_) {
-    handler->TextHook(text);
-  }
+  text_input_plugin_->TextHook(text);
 }
 
 bool FlutterWindowsView::SendKey(int key,
@@ -392,39 +390,32 @@ bool FlutterWindowsView::SendKey(int key,
                                  char32_t character,
                                  bool extended,
                                  bool was_down) {
-  for (const auto& handler : keyboard_handlers_) {
-    if (handler->KeyboardHook(key, scancode, action, character, extended,
-                              was_down)) {
-      // key event was handled, so don't send to other handlers.
-      return true;
-    }
+  if (keyboard_key_handler_->KeyboardHook(key, scancode, action, character,
+                                          extended, was_down)) {
+    return true;
   }
+
+  text_input_plugin_->KeyboardHook(key, scancode, action, character, extended,
+                                   was_down);
+
   return false;
 }
 
 void FlutterWindowsView::SendComposeBegin() {
-  for (const auto& handler : keyboard_handlers_) {
-    handler->ComposeBeginHook();
-  }
+  text_input_plugin_->ComposeBeginHook();
 }
 
 void FlutterWindowsView::SendComposeCommit() {
-  for (const auto& handler : keyboard_handlers_) {
-    handler->ComposeCommitHook();
-  }
+  text_input_plugin_->ComposeCommitHook();
 }
 
 void FlutterWindowsView::SendComposeEnd() {
-  for (const auto& handler : keyboard_handlers_) {
-    handler->ComposeEndHook();
-  }
+  text_input_plugin_->ComposeEndHook();
 }
 
 void FlutterWindowsView::SendComposeChange(const std::u16string& text,
                                            int cursor_pos) {
-  for (const auto& handler : keyboard_handlers_) {
-    handler->ComposeChangeHook(text, cursor_pos);
-  }
+  text_input_plugin_->ComposeChangeHook(text, cursor_pos);
 }
 
 void FlutterWindowsView::SendScroll(double x,
diff --git a/shell/platform/windows/flutter_windows_view.h b/shell/platform/windows/flutter_windows_view.h
index e9a542cb5970e..4a9b9a4c15558 100644
--- a/shell/platform/windows/flutter_windows_view.h
+++ b/shell/platform/windows/flutter_windows_view.h
@@ -22,9 +22,9 @@
 #include "flutter/shell/platform/windows/flutter_windows_engine.h"
 #include "flutter/shell/platform/windows/keyboard_handler_base.h"
 #include "flutter/shell/platform/windows/keyboard_key_embedder_handler.h"
-#include "flutter/shell/platform/windows/keyboard_key_handler.h"
 #include "flutter/shell/platform/windows/platform_handler.h"
 #include "flutter/shell/platform/windows/public/flutter_windows.h"
+#include "flutter/shell/platform/windows/text_input_plugin.h"
 #include "flutter/shell/platform/windows/text_input_plugin_delegate.h"
 #include "flutter/shell/platform/windows/window_binding_handler.h"
 #include "flutter/shell/platform/windows/window_binding_handler_delegate.h"
@@ -171,20 +171,20 @@ class FlutterWindowsView : public WindowBindingHandlerDelegate,
   void OnResetImeComposing() override;
 
  protected:
-  // Called to create the keyboard hook handlers.
+  // Called to create keyboard key handler.
   //
   // The provided |dispatch_event| is where to inject events into the system,
   // while |get_key_state| is where to acquire keyboard states. They will be
   // the system APIs in production classes, but might be replaced with mock
   // functions in unit tests.
-  virtual void RegisterKeyboardHandlers(
-      flutter::BinaryMessenger* messenger,
-      flutter::KeyboardKeyHandler::EventDispatcher dispatch_event,
-      flutter::KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state);
+  virtual std::unique_ptr<KeyboardHandlerBase> CreateKeyboardKeyHandler(
+      BinaryMessenger* messenger,
+      KeyboardKeyHandler::EventDispatcher dispatch_event,
+      KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state);
 
-  // Used by RegisterKeyboardHandlers to add a new keyboard hook handler.
-  void AddKeyboardHandler(
-      std::unique_ptr<flutter::KeyboardHandlerBase> handler);
+  // Called to create text input plugin.
+  virtual std::unique_ptr<TextInputPlugin> CreateTextInputPlugin(
+      BinaryMessenger* messenger);
 
  private:
   // Struct holding the state of an individual pointer. The engine doesn't keep
@@ -322,19 +322,22 @@ class FlutterWindowsView : public WindowBindingHandlerDelegate,
   std::unordered_map<int32_t, std::unique_ptr<PointerState>> pointer_states_;
 
   // The plugin registrar managing internal plugins.
-  std::unique_ptr<flutter::PluginRegistrar> internal_plugin_registrar_;
+  std::unique_ptr<PluginRegistrar> internal_plugin_registrar_;
 
   // Handlers for keyboard events from Windows.
-  std::vector<std::unique_ptr<flutter::KeyboardHandlerBase>> keyboard_handlers_;
+  std::unique_ptr<KeyboardHandlerBase> keyboard_key_handler_;
+
+  // Handlers for text events from Windows.
+  std::unique_ptr<TextInputPlugin> text_input_plugin_;
 
   // Handler for the flutter/platform channel.
-  std::unique_ptr<flutter::PlatformHandler> platform_handler_;
+  std::unique_ptr<PlatformHandler> platform_handler_;
 
   // Handler for cursor events.
-  std::unique_ptr<flutter::CursorHandler> cursor_handler_;
+  std::unique_ptr<CursorHandler> cursor_handler_;
 
   // Currently configured WindowBindingHandler for view.
-  std::unique_ptr<flutter::WindowBindingHandler> binding_handler_;
+  std::unique_ptr<WindowBindingHandler> binding_handler_;
 
   // Resize events are synchronized using this mutex and the corresponding
   // condition variable.
diff --git a/shell/platform/windows/keyboard_handler_base.h b/shell/platform/windows/keyboard_handler_base.h
index db4e92dbb3d02..4e7b5c44ba4a7 100644
--- a/shell/platform/windows/keyboard_handler_base.h
+++ b/shell/platform/windows/keyboard_handler_base.h
@@ -29,35 +29,6 @@ class KeyboardHandlerBase {
                             char32_t character,
                             bool extended,
                             bool was_down) = 0;
-
-  // A function for hooking into Unicode text input.
-  virtual void TextHook(const std::u16string& text) = 0;
-
-  // Handler for IME compose begin events.
-  //
-  // Triggered when the user begins editing composing text using a multi-step
-  // input method such as in CJK text input.
-  virtual void ComposeBeginHook() = 0;
-
-  // Handler for IME compose commit events.
-  //
-  // Triggered when the user commits the current composing text while using a
-  // multi-step input method such as in CJK text input. Composing continues with
-  // the next keypress.
-  virtual void ComposeCommitHook() = 0;
-
-  // Handler for IME compose end events.
-  //
-  // Triggered when the user ends editing composing text while using a
-  // multi-step input method such as in CJK text input.
-  virtual void ComposeEndHook() = 0;
-
-  // Handler for IME compose change events.
-  //
-  // Triggered when the user edits the composing text while using a multi-step
-  // input method such as in CJK text input.
-  virtual void ComposeChangeHook(const std::u16string& text,
-                                 int cursor_pos) = 0;
 };
 
 }  // namespace flutter
diff --git a/shell/platform/windows/keyboard_key_handler.cc b/shell/platform/windows/keyboard_key_handler.cc
index bb47b21736bb5..50e669aff6a40 100644
--- a/shell/platform/windows/keyboard_key_handler.cc
+++ b/shell/platform/windows/keyboard_key_handler.cc
@@ -109,8 +109,6 @@ KeyboardKeyHandler::KeyboardKeyHandler(EventDispatcher dispatch_event)
 
 KeyboardKeyHandler::~KeyboardKeyHandler() = default;
 
-void KeyboardKeyHandler::TextHook(const std::u16string& code_point) {}
-
 void KeyboardKeyHandler::AddDelegate(
     std::unique_ptr<KeyboardKeyHandlerDelegate> delegate) {
   delegates_.push_back(std::move(delegate));
@@ -291,23 +289,6 @@ void KeyboardKeyHandler::ResolvePendingEvent(uint64_t sequence_id,
   assert(false);
 }
 
-void KeyboardKeyHandler::ComposeBeginHook() {
-  // Ignore.
-}
-
-void KeyboardKeyHandler::ComposeCommitHook() {
-  // Ignore.
-}
-
-void KeyboardKeyHandler::ComposeEndHook() {
-  // Ignore.
-}
-
-void KeyboardKeyHandler::ComposeChangeHook(const std::u16string& text,
-                                           int cursor_pos) {
-  // Ignore.
-}
-
 uint64_t KeyboardKeyHandler::ComputeEventHash(const PendingEvent& event) {
   // Calculate a key event ID based on the scan code of the key pressed,
   // and the flags we care about.
diff --git a/shell/platform/windows/keyboard_key_handler.h b/shell/platform/windows/keyboard_key_handler.h
index 39de8366e0a2c..0f1217815d754 100644
--- a/shell/platform/windows/keyboard_key_handler.h
+++ b/shell/platform/windows/keyboard_key_handler.h
@@ -96,21 +96,6 @@ class KeyboardKeyHandler : public KeyboardHandlerBase {
                     bool extended,
                     bool was_down) override;
 
-  // |KeyboardHandlerBase|
-  void TextHook(const std::u16string& text) override;
-
-  // |KeyboardHandlerBase|
-  void ComposeBeginHook() override;
-
-  // |KeyboardHandlerBase|
-  void ComposeCommitHook() override;
-
-  // |KeyboardHandlerBase|
-  void ComposeEndHook() override;
-
-  // |KeyboardHandlerBase|
-  void ComposeChangeHook(const std::u16string& text, int cursor_pos) override;
-
  protected:
   size_t RedispatchedCount();
 
diff --git a/shell/platform/windows/keyboard_win32_unittests.cc b/shell/platform/windows/keyboard_win32_unittests.cc
index 2be6885057810..00e5767d52daa 100644
--- a/shell/platform/windows/keyboard_win32_unittests.cc
+++ b/shell/platform/windows/keyboard_win32_unittests.cc
@@ -190,11 +190,11 @@ class TestFlutterWindowsView : public FlutterWindowsView {
   }
 
  protected:
-  void RegisterKeyboardHandlers(
+  std::unique_ptr<KeyboardHandlerBase> CreateKeyboardKeyHandler(
       BinaryMessenger* messenger,
       KeyboardKeyHandler::EventDispatcher dispatch_event,
       KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state) override {
-    FlutterWindowsView::RegisterKeyboardHandlers(
+    return FlutterWindowsView::CreateKeyboardKeyHandler(
         messenger,
         [this](UINT cInputs, LPINPUT pInputs, int cbSize) -> UINT {
           return this->SendInput(cInputs, pInputs, cbSize);
diff --git a/shell/platform/windows/text_input_plugin.cc b/shell/platform/windows/text_input_plugin.cc
index 93b538ccb7d98..15e497e512de0 100644
--- a/shell/platform/windows/text_input_plugin.cc
+++ b/shell/platform/windows/text_input_plugin.cc
@@ -58,14 +58,14 @@ void TextInputPlugin::TextHook(const std::u16string& text) {
   SendStateUpdate(*active_model_);
 }
 
-bool TextInputPlugin::KeyboardHook(int key,
+void TextInputPlugin::KeyboardHook(int key,
                                    int scancode,
                                    int action,
                                    char32_t character,
                                    bool extended,
                                    bool was_down) {
   if (active_model_ == nullptr) {
-    return false;
+    return;
   }
   if (action == WM_KEYDOWN || action == WM_SYSKEYDOWN) {
     // Most editing keys (arrow keys, backspace, delete, etc.) are handled in
@@ -78,7 +78,6 @@ bool TextInputPlugin::KeyboardHook(int key,
         break;
     }
   }
-  return false;
 }
 
 TextInputPlugin::TextInputPlugin(flutter::BinaryMessenger* messenger,
diff --git a/shell/platform/windows/text_input_plugin.h b/shell/platform/windows/text_input_plugin.h
index 7b3d487675160..664690e185836 100644
--- a/shell/platform/windows/text_input_plugin.h
+++ b/shell/platform/windows/text_input_plugin.h
@@ -22,35 +22,29 @@ namespace flutter {
 // Implements a text input plugin.
 //
 // Specifically handles window events within windows.
-class TextInputPlugin : public KeyboardHandlerBase {
+class TextInputPlugin {
  public:
   explicit TextInputPlugin(flutter::BinaryMessenger* messenger,
                            TextInputPluginDelegate* delegate);
 
   virtual ~TextInputPlugin();
 
-  // |KeyboardHandlerBase|
-  bool KeyboardHook(int key,
+  virtual void KeyboardHook(int key,
                     int scancode,
                     int action,
                     char32_t character,
                     bool extended,
-                    bool was_down) override;
+                    bool was_down);
 
-  // |KeyboardHandlerBase|
-  void TextHook(const std::u16string& text) override;
+  virtual void TextHook(const std::u16string& text);
 
-  // |KeyboardHandlerBase|
-  void ComposeBeginHook() override;
+  virtual void ComposeBeginHook();
 
-  // |KeyboardHandlerBase|
-  void ComposeCommitHook() override;
+  virtual void ComposeCommitHook();
 
-  // |KeyboardHandlerBase|
-  void ComposeEndHook() override;
+  virtual void ComposeEndHook();
 
-  // |KeyboardHandlerBase|
-  void ComposeChangeHook(const std::u16string& text, int cursor_pos) override;
+  virtual void ComposeChangeHook(const std::u16string& text, int cursor_pos);
 
  private:
   // Sends the current state of the given model to the Flutter engine.

From bd3a95d1846e4d088f6a53e56211e386e9d165a7 Mon Sep 17 00:00:00 2001
From: Tong Mu <dkwingsmt@gmail.com>
Date: Wed, 22 Dec 2021 00:23:57 -0800
Subject: [PATCH 2/3] format

---
 .../windows/flutter_window_win32_unittests.cc       |  3 +--
 shell/platform/windows/flutter_windows_view.cc      | 13 ++++++-------
 shell/platform/windows/text_input_plugin.h          | 10 +++++-----
 3 files changed, 12 insertions(+), 14 deletions(-)

diff --git a/shell/platform/windows/flutter_window_win32_unittests.cc b/shell/platform/windows/flutter_window_win32_unittests.cc
index 0968ac0a2f51a..55e538433d320 100644
--- a/shell/platform/windows/flutter_window_win32_unittests.cc
+++ b/shell/platform/windows/flutter_window_win32_unittests.cc
@@ -36,8 +36,7 @@ class SpyKeyboardKeyHandler : public KeyboardHandlerBase {
  public:
   SpyKeyboardKeyHandler(flutter::BinaryMessenger* messenger,
                         KeyboardKeyHandler::EventDispatcher dispatch_event) {
-    real_implementation_ =
-        std::make_unique<KeyboardKeyHandler>(dispatch_event);
+    real_implementation_ = std::make_unique<KeyboardKeyHandler>(dispatch_event);
     real_implementation_->AddDelegate(
         std::make_unique<KeyboardKeyChannelHandler>(messenger));
     ON_CALL(*this, KeyboardHook(_, _, _, _, _, _))
diff --git a/shell/platform/windows/flutter_windows_view.cc b/shell/platform/windows/flutter_windows_view.cc
index ee60f12676894..e4fe3b287de08 100644
--- a/shell/platform/windows/flutter_windows_view.cc
+++ b/shell/platform/windows/flutter_windows_view.cc
@@ -58,8 +58,8 @@ void FlutterWindowsView::SetEngine(
   auto internal_plugin_messenger = internal_plugin_registrar_->messenger();
   InitializeKeyboard();
   platform_handler_ = PlatformHandler::Create(internal_plugin_messenger, this);
-  cursor_handler_ = std::make_unique<CursorHandler>(
-      internal_plugin_messenger, binding_handler_.get());
+  cursor_handler_ = std::make_unique<CursorHandler>(internal_plugin_messenger,
+                                                    binding_handler_.get());
 
   PhysicalWindowBounds bounds = binding_handler_->GetPhysicalWindowBounds();
 
@@ -80,7 +80,8 @@ FlutterWindowsView::CreateKeyboardKeyHandler(
   // of the event. In order to allow the same real event in the future, the
   // handler is "toggled" when events pass through, therefore the redispatching
   // algorithm does not allow more than 1 handler that takes |SendInput|.
-  auto keyboard_key_handler = std::make_unique<KeyboardKeyHandler>(dispatch_event);
+  auto keyboard_key_handler =
+      std::make_unique<KeyboardKeyHandler>(dispatch_event);
   keyboard_key_handler->AddDelegate(
       std::make_unique<KeyboardKeyEmbedderHandler>(
           [this](const FlutterKeyEvent& event, FlutterKeyEventCallback callback,
@@ -267,12 +268,10 @@ void FlutterWindowsView::InitializeKeyboard() {
   auto internal_plugin_messenger = internal_plugin_registrar_->messenger();
 #ifdef WINUWP
   KeyboardKeyHandler::EventDispatcher dispatch_event = nullptr;
-  KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state =
-      nullptr;
+  KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state = nullptr;
 #else
   KeyboardKeyHandler::EventDispatcher dispatch_event = SendInput;
-  KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state =
-      GetKeyState;
+  KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state = GetKeyState;
 #endif
   keyboard_key_handler_ = std::move(CreateKeyboardKeyHandler(
       internal_plugin_messenger, dispatch_event, get_key_state));
diff --git a/shell/platform/windows/text_input_plugin.h b/shell/platform/windows/text_input_plugin.h
index 664690e185836..ad8a131b9f600 100644
--- a/shell/platform/windows/text_input_plugin.h
+++ b/shell/platform/windows/text_input_plugin.h
@@ -30,11 +30,11 @@ class TextInputPlugin {
   virtual ~TextInputPlugin();
 
   virtual void KeyboardHook(int key,
-                    int scancode,
-                    int action,
-                    char32_t character,
-                    bool extended,
-                    bool was_down);
+                            int scancode,
+                            int action,
+                            char32_t character,
+                            bool extended,
+                            bool was_down);
 
   virtual void TextHook(const std::u16string& text);
 

From 610d6c80629a07c16f7d58c8fa07c93ad7f5e622 Mon Sep 17 00:00:00 2001
From: Tong Mu <dkwingsmt@gmail.com>
Date: Wed, 5 Jan 2022 03:21:26 -0800
Subject: [PATCH 3/3] Comment

---
 .../windows/flutter_window_win32_unittests.cc       | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/shell/platform/windows/flutter_window_win32_unittests.cc b/shell/platform/windows/flutter_window_win32_unittests.cc
index 55e538433d320..a35e10d9f345a 100644
--- a/shell/platform/windows/flutter_window_win32_unittests.cc
+++ b/shell/platform/windows/flutter_window_win32_unittests.cc
@@ -247,19 +247,20 @@ class TestFlutterWindowsView : public FlutterWindowsView {
       flutter::KeyboardKeyHandler::EventDispatcher dispatch_event,
       flutter::KeyboardKeyEmbedderHandler::GetKeyStateHandler get_key_state)
       override {
-    auto spy_key_event_handler = new SpyKeyboardKeyHandler(
+    auto spy_key_event_handler = std::make_unique<SpyKeyboardKeyHandler>(
         messenger, [this](UINT cInputs, LPINPUT pInputs, int cbSize) -> UINT {
           return this->SendInput(cInputs, pInputs, cbSize);
         });
-    key_event_handler = spy_key_event_handler;
-    return std::unique_ptr<KeyboardHandlerBase>(spy_key_event_handler);
+    key_event_handler = spy_key_event_handler.get();
+    return spy_key_event_handler;
   }
 
   std::unique_ptr<TextInputPlugin> CreateTextInputPlugin(
       flutter::BinaryMessenger* messenger) override {
-    auto spy_key_event_handler = new SpyTextInputPlugin(messenger);
-    text_input_plugin = spy_key_event_handler;
-    return std::unique_ptr<TextInputPlugin>(spy_key_event_handler);
+    auto spy_key_event_handler =
+        std::make_unique<SpyTextInputPlugin>(messenger);
+    text_input_plugin = spy_key_event_handler.get();
+    return spy_key_event_handler;
   }
 
  private: