Remove calls to SkCanvas::flush() (#43684)

In https://skia-review.googlesource.com/c/skia/+/716476, Skia removed
calls to SkCanvas::flush(). This replaces those calls that Flutter was
making with what had been going on - calling GrDirectContext::flush() if
the canvas was backed by a Ganesh backend. Raster-backed canvases did
not need flushing.

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Author: kjlubick

display_list/skia/dl_sk_canvas.cc

@@ -9,6 +9,8 @@
 #include "flutter/fml/trace_event.h"
 
 #include "third_party/skia/include/core/SkColorFilter.h"
+#include "third_party/skia/include/gpu/GrDirectContext.h"
+#include "third_party/skia/include/gpu/GrRecordingContext.h"
 
 namespace flutter {
 
@@ -374,7 +376,11 @@ void DlSkCanvasAdapter::DrawShadow(const SkPath& path,
 }
 
 void DlSkCanvasAdapter::Flush() {
-  delegate_->flush();
+  auto dContext = GrAsDirectContext(delegate_->recordingContext());
+
+  if (dContext) {
+    dContext->flushAndSubmit();
+  }
 }
 
 }  // namespace flutter

display_list/testing/dl_rendering_unittests.cc

@@ -492,7 +492,6 @@ class RenderEnvironment {
     renderer.Render(canvas, info);
     canvas->restoreToCount(restore_count);
 
-    canvas->flush();
     if (GrDirectContext* dContext =
             GrAsDirectContext(surface->recordingContext())) {
       dContext->flushAndSubmit(surface, /*syncCpu=*/true);

lib/ui/painting/image_encoding_impl.h

@@ -9,6 +9,7 @@
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkImage.h"
 #include "third_party/skia/include/core/SkSurface.h"
+#include "third_party/skia/include/gpu/GrDirectContext.h"
 #include "third_party/skia/include/gpu/ganesh/SkSurfaceGanesh.h"
 
 namespace flutter {
@@ -41,7 +42,9 @@ sk_sp<SkImage> ConvertToRasterUsingResourceContext(
   }
 
   surface->getCanvas()->drawImage(image, 0, 0);
-  surface->getCanvas()->flush();
+  if (resource_context) {
+    resource_context->flushAndSubmit();
+  }
 
   auto snapshot = surface->makeImageSnapshot();
 

shell/common/rasterizer_unittests.cc

@@ -990,7 +990,6 @@ TEST(RasterizerTest, TeardownFreesResourceCache) {
 
   SkPaint paint;
   sk_surface->getCanvas()->drawPaint(paint);
-  sk_surface->getCanvas()->flush();
   context->flushAndSubmit(true);
 
   EXPECT_EQ(context->getResourceCachePurgeableBytes(), 0ul);

shell/common/snapshot_controller_skia.cc

@@ -23,7 +23,10 @@ sk_sp<SkImage> DrawSnapshot(
   }
 
   draw_callback(surface->getCanvas());
-  surface->getCanvas()->flush();
+  auto dContext = GrAsDirectContext(surface->recordingContext());
+  if (dContext) {
+    dContext->flushAndSubmit();
+  }
 
   sk_sp<SkImage> device_snapshot;
   {

shell/gpu/gpu_surface_gl_skia.cc

@@ -268,8 +268,8 @@ bool GPUSurfaceGLSkia::PresentSurface(const SurfaceFrame& frame,
   delegate_->GLContextSetDamageRegion(frame.submit_info().buffer_damage);
 
   {
-    TRACE_EVENT0("flutter", "SkCanvas::Flush");
-    onscreen_surface_->getCanvas()->flush();
+    TRACE_EVENT0("flutter", "GrDirectContext::flushAndSubmit");
+    context_->flushAndSubmit();
   }
 
   GLPresentInfo present_info = {

shell/platform/fuchsia/flutter/canvas_spy.cc

@@ -267,6 +267,4 @@ void DidDrawCanvas::onDrawEdgeAAImageSet2(const ImageSetEntry set[],
   did_draw_ = true;
 }
 
-void DidDrawCanvas::onFlush() {}
-
 }  // namespace flutter

shell/platform/fuchsia/flutter/canvas_spy.h

@@ -248,9 +248,6 @@ class DidDrawCanvas final : public SkCanvasVirtualEnforcer<SkNoDrawCanvas> {
                              const SkPaint*,
                              SrcRectConstraint) override;
 
-  // |SkCanvasVirtualEnforcer<SkNoDrawCanvas>|
-  void onFlush() override;
-
   void MarkDrawIfNonTransparentPaint(const SkPaint& paint);
 
   FML_DISALLOW_COPY_AND_ASSIGN(DidDrawCanvas);