Reland "Not disable acceleration in getImage if its Desynchronized"

This reverts commit 49fa3eb.

Reason for revert: Fixing Pixel test.

Original change's description:
> Revert "Not disable acceleration in getImage if its Desynchronized"
>
> This reverts commit edce90d.
>
> Reason for revert: crbug.com/1151440 Pixel_CanvasLowLatency2DImageData
> test consistently fails on Android FYI Release builders, e.g.:
>
> https://ci.chromium.org/p/chromium/builders/ci/Android%20FYI%20Release%20%28Nexus%205%29/b8863094711783933776
>
> Original change's description:
> > Not disable acceleration in getImage if its Desynchronized
> >
> > This is a temporary fix for this issue, that will totally be fixed
> > after we land the new 2d canvas api (that will completely remove the
> > path of code causing this regression in base_rendering_context_2d.cc:
> >   if (!RuntimeEnabledFeatures::NewCanvas2DAPIEnabled()) {
> >     // GetImagedata is faster in Unaccelerated canvases
> >     // Do not disaccelerate if Desync2d Canvas on android.
> >     // Issue 1112060: putImageData() does not work for desynchronized 2D canvas
> >     // on Android
> >     if (IsAccelerated()) {
> >       DisableAcceleration();
> >       base::UmaHistogramEnumeration("Blink.Canvas.GPUFallbackToCPU",
> >                                     GPUFallbackToCPUScenario::kGetImageData);
> >     }
> >   }
> >
> > This CL specifically disables that path if the canvas is Desynchronized.
> > To do so this CL adds some infrastructural elements to be able to access
> > to the desynchronization setting inside getImage.
> >
> > This issue is only happening in a very specific corner case, which
> > proves hard to be tested. This code will be deleted once we enable
> > the new canvas api - so this is a temporary fix.
> >
> > Bug: 1112060
> > Change-Id: I60b90f716332b3969c82dfef3431e4cbd66e6500
> > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2541063
> > Reviewed-by: Aaron Krajeski <aaronhk@chromium.org>
> > Commit-Queue: Juanmi Huertas <juanmihd@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#829679}
>
> TBR=fserb@chromium.org,aaronhk@chromium.org,juanmihd@chromium.org
>
> Change-Id: I35417b2a319a610b7aec7123112db153cff3a806
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: 1112060
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2552924
> Commit-Queue: Mingjing Zhang <mjzhang@chromium.org>
> Reviewed-by: Mingjing Zhang <mjzhang@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#829801}

TBR=fserb@chromium.org,aaronhk@chromium.org,juanmihd@chromium.org,mjzhang@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1112060, 1151440
Change-Id: Ic2dae93db31fd8d6ae107db21373468b3ae7cfe5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2553699
Reviewed-by: Aaron Krajeski <aaronhk@chromium.org>
Reviewed-by: Fernando Serboncini <fserb@chromium.org>
Commit-Queue: Juanmi Huertas <juanmihd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#831120}

third_party/blink/renderer/modules/canvas/canvas2d/base_rendering_context_2d.cc

@@ -1696,12 +1696,14 @@ ImageData* BaseRenderingContext2D::getImageDataInternal(
 
   // TODO(crbug.com/1101055): Remove the check for NewCanvas2DAPI flag once
   // released.
-  // New Canvas2D API utilizes willReadFrequently attribute that let the users
-  // indicate if a canvas will be read frequently through getImageData, thus
-  // uses CPU rendering from the start in such cases. (crbug.com/1090180)
+  // TODO(crbug.com/1090180): New Canvas2D API utilizes willReadFrequently
+  // attribute that let the users indicate if a canvas will be read frequently
+  // through getImageData, thus uses CPU rendering from the start in such cases.
   if (!RuntimeEnabledFeatures::NewCanvas2DAPIEnabled()) {
-    // GetImagedata is faster in Unaccelerated canvases
-    if (IsAccelerated()) {
+    // GetImagedata is faster in Unaccelerated canvases.
+    // In Desynchronized canvas disabling the acceleration will break
+    // putImageData: crbug.com/1112060.
+    if (IsAccelerated() && !IsDesynchronized()) {
       DisableAcceleration();
       base::UmaHistogramEnumeration("Blink.Canvas.GPUFallbackToCPU",
                                     GPUFallbackToCPUScenario::kGetImageData);

third_party/blink/renderer/modules/canvas/canvas2d/base_rendering_context_2d.h

@@ -253,6 +253,11 @@ class MODULES_EXPORT BaseRenderingContext2D : public GarbageCollectedMixin,
 
   virtual bool HasAlpha() const = 0;
 
+  virtual bool IsDesynchronized() const {
+    NOTREACHED();
+    return false;
+  }
+
   virtual bool isContextLost() const = 0;
 
   virtual void WillDrawImage(CanvasImageSource*) const {}

third_party/blink/renderer/modules/canvas/canvas2d/canvas_rendering_context_2d.h

@@ -278,6 +278,9 @@ class MODULES_EXPORT CanvasRenderingContext2D final
   bool IsAccelerated() const override;
   bool IsOriginTopLeft() const override;
   bool HasAlpha() const override { return CreationAttributes().alpha; }
+  bool IsDesynchronized() const override {
+    return CreationAttributes().desynchronized;
+  }
   void SetIsInHiddenPage(bool) override;
   void SetIsBeingDisplayed(bool) override;
   void Stop() final;

third_party/blink/renderer/modules/canvas/offscreencanvas2d/offscreen_canvas_rendering_context_2d.h

@@ -122,6 +122,9 @@ class MODULES_EXPORT OffscreenCanvasRenderingContext2D final
   void ValidateStateStackWithCanvas(const cc::PaintCanvas*) const final;
 
   bool HasAlpha() const final { return CreationAttributes().alpha; }
+  bool IsDesynchronized() const final {
+    return CreationAttributes().desynchronized;
+  }
   bool isContextLost() const override;
 
   ImageBitmap* TransferToImageBitmap(ScriptState*) final;