[iOS] clean ups to platform view controller

ci/licenses_golden/licenses_flutter

@@ -43655,7 +43655,6 @@ ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterOverl
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformPlugin.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformPlugin.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformPluginTest.mm + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViewsTest.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.mm + ../../../flutter/LICENSE
@@ -43713,8 +43712,12 @@ ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/availability
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/connection_collection.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/connection_collection.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/connection_collection_test.mm + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/overlay_layer_pool.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/overlay_layer_pool.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_message_response_darwin.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_message_response_darwin.mm + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_views_controller.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_views_controller.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/profiler_metrics_ios.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/profiler_metrics_ios.mm + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/darwin/ios/framework/Source/vsync_waiter_ios.h + ../../../flutter/LICENSE
@@ -46559,7 +46562,6 @@ FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterOverlay
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformPlugin.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformPlugin.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformPluginTest.mm
-FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViewsTest.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.mm
@@ -46617,8 +46619,12 @@ FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/availability_v
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/connection_collection.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/connection_collection.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/connection_collection_test.mm
+FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/overlay_layer_pool.h
+FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/overlay_layer_pool.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_message_response_darwin.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_message_response_darwin.mm
+FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_views_controller.h
+FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/platform_views_controller.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/profiler_metrics_ios.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/profiler_metrics_ios.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Source/vsync_waiter_ios.h

shell/platform/darwin/ios/BUILD.gn

@@ -77,7 +77,6 @@ source_set("flutter_framework_source_arc") {
     "framework/Source/FlutterMetalLayer.mm",
     "framework/Source/FlutterOverlayView.h",
     "framework/Source/FlutterOverlayView.mm",
-    "framework/Source/FlutterPlatformViews.mm",
     "framework/Source/FlutterPlatformViews_Internal.h",
     "framework/Source/FlutterPlatformViews_Internal.mm",
     "framework/Source/FlutterPluginAppLifeCycleDelegate.mm",
@@ -110,8 +109,12 @@ source_set("flutter_framework_source_arc") {
     "framework/Source/UIViewController+FlutterScreenAndSceneIfLoaded.mm",
     "framework/Source/connection_collection.h",
     "framework/Source/connection_collection.mm",
+    "framework/Source/overlay_layer_pool.h",
+    "framework/Source/overlay_layer_pool.mm",
     "framework/Source/platform_message_response_darwin.h",
     "framework/Source/platform_message_response_darwin.mm",
+    "framework/Source/platform_views_controller.h",
+    "framework/Source/platform_views_controller.mm",
     "framework/Source/profiler_metrics_ios.h",
     "framework/Source/profiler_metrics_ios.mm",
     "framework/Source/vsync_waiter_ios.h",

shell/platform/darwin/ios/framework/Source/FlutterEngine.mm

@@ -123,7 +123,7 @@ @implementation FlutterEngine {
   fml::WeakNSObject<FlutterViewController> _viewController;
   fml::scoped_nsobject<FlutterDartVMServicePublisher> _publisher;
 
-  std::shared_ptr<flutter::FlutterPlatformViewsController> _platformViewsController;
+  std::shared_ptr<flutter::PlatformViewsController> _platformViewsController;
   flutter::IOSRenderingAPI _renderingApi;
   std::shared_ptr<flutter::ProfilerMetricsIOS> _profiler_metrics;
   std::shared_ptr<flutter::SamplingProfiler> _profiler;
@@ -271,7 +271,7 @@ - (void)setUpApplicationLifecycleNotifications:(NSNotificationCenter*)center {
 
 - (void)recreatePlatformViewController {
   _renderingApi = flutter::GetRenderingAPIForProcess(FlutterView.forceSoftwareRendering);
-  _platformViewsController.reset(new flutter::FlutterPlatformViewsController());
+  _platformViewsController.reset(new flutter::PlatformViewsController());
 }
 
 - (flutter::IOSRenderingAPI)platformViewsRenderingAPI {
@@ -495,7 +495,7 @@ - (FlutterViewController*)viewController {
 - (FlutterPlatformPlugin*)platformPlugin {
   return _platformPlugin.get();
 }
-- (std::shared_ptr<flutter::FlutterPlatformViewsController>&)platformViewsController {
+- (std::shared_ptr<flutter::PlatformViewsController>&)platformViewsController {
   return _platformViewsController;
 }
 - (FlutterTextInputPlugin*)textInputPlugin {

shell/platform/darwin/ios/framework/Source/FlutterEngine_Internal.h

@@ -48,7 +48,7 @@ extern NSString* const kFlutterEngineWillDealloc;
                                  base64Encode:(bool)base64Encode;
 
 - (FlutterPlatformPlugin*)platformPlugin;
-- (std::shared_ptr<flutter::FlutterPlatformViewsController>&)platformViewsController;
+- (std::shared_ptr<flutter::PlatformViewsController>&)platformViewsController;
 - (FlutterTextInputPlugin*)textInputPlugin;
 - (FlutterRestorationPlugin*)restorationPlugin;
 - (void)launchEngine:(nullable NSString*)entrypoint