mac: Use IOSurfaces in Canvas2DLayerBridge.

content/child/runtime_features.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/child/runtime_features.h"
 
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/feature_list.h"
@@ skipping 89 matching lines @@
 
   if (command_line.HasSwitch(switches::kDisableDisplayList2dCanvas))
     WebRuntimeFeatures::enableDisplayList2dCanvas(false);
 
   if (command_line.HasSwitch(switches::kForceDisplayList2dCanvas))
     WebRuntimeFeatures::forceDisplayList2dCanvas(true);
 
   if (command_line.HasSwitch(switches::kEnableWebGLDraftExtensions))
     WebRuntimeFeatures::enableWebGLDraftExtensions(true);
 
+#if defined(OS_MACOSX)
+  bool enable_canvas_2d_image_chromium = command_line.HasSwitch(
+      switches::kEnableGpuMemoryBufferCompositorResources) &&
+      !command_line.HasSwitch(switches::kDisable2dCanvasImageChromium) &&
+      !command_line.HasSwitch(switches::kDisableGpu);
+#else
+  bool enable_canvas_2d_image_chromium = false;
+#endif
+  WebRuntimeFeatures::enableCanvas2dImageChromium(
+      enable_canvas_2d_image_chromium);

[Ken Russell (switch to Gerrit), 2016/03/10 02:00:04]

I think you should add a new GPU driver bug workaround type covering this
feature, so that if you find that it's broken on a particular kind of GPU, you
can easily disable it there. Please see
src/gpu/config/gpu_driver_bug_list_json.cc and
src/gpu/config/gpu_driver_bug_workaround_type.h , and uses of these workaround
types.

+
   if (command_line.HasSwitch(switches::kEnableWebGLImageChromium))
     WebRuntimeFeatures::enableWebGLImageChromium(true);
 
   if (command_line.HasSwitch(switches::kForceOverlayFullscreenVideo))
     WebRuntimeFeatures::forceOverlayFullscreenVideo(true);
 
   if (ui::IsOverlayScrollbarEnabled())
     WebRuntimeFeatures::enableOverlayScrollbars(true);
 
   if (command_line.HasSwitch(switches::kEnablePreciseMemoryInfo))
@@ skipping 58 matching lines @@
   if (command_line.HasSwitch(switches::kDisableBlinkFeatures)) {
     std::vector<std::string> disabled_features = base::SplitString(
         command_line.GetSwitchValueASCII(switches::kDisableBlinkFeatures),
         ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
     for (const std::string& feature : disabled_features)
       WebRuntimeFeatures::enableFeatureFromString(feature, false);
   }
 }
 
 }  // namespace content