[Merge to 2704] Turn off IOSurface implementation for Canvas2D.

third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h

Index: third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
diff --git a/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h b/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
index 0dd0adee365d5f3f51a9e7dc748a27307886d34b..ab896e00a0ad2636110f8b17f1b11474eaf198f1 100644
--- a/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
+++ b/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h
@@ -66,7 +66,10 @@ class SharedContextRateLimiter;
 #define CANVAS2D_HIBERNATION_ENABLED 0
 
 // IOSurfaces are a primitive only present on OS X.
-#define USE_IOSURFACE_FOR_2D_CANVAS 1
+// IOSurfaces can't be used right now because the compositor returns them while
+// they are they still in use by the Window Server, and the SyncToken isn't
+// relevant. https://crbug.com/608026.
+#define USE_IOSURFACE_FOR_2D_CANVAS 0
 #else
 #define CANVAS2D_HIBERNATION_ENABLED 1
 #define USE_IOSURFACE_FOR_2D_CANVAS 0