Speculative fix for 2D canvas crash on Mac

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

Index: third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.cpp b/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.cpp
index 51642005bec56d5bf60742d918cc6f13f9a27323..fa456f815d812ec294adace6b837164411be2d8f 100644
--- a/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.cpp
+++ b/third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.cpp
@@ -603,7 +603,7 @@ bool Canvas2DLayerBridge::prepareMailbox(WebExternalTextureMailbox* outMailbox,
     }
 
     RefPtr<SkImage> image = newImageSnapshot(PreferAcceleration);
-    if (!image)
+    if (!image || !image->getTexture())
         return false;
 
     WebGraphicsContext3D* webContext = context();
@@ -635,8 +635,6 @@ bool Canvas2DLayerBridge::prepareMailbox(WebExternalTextureMailbox* outMailbox,
     // Need to flush skia's internal queue because texture is about to be accessed directly
     grContext->flush();
 
-    ASSERT(image->getTexture());
-
     // Because of texture sharing with the compositor, we must invalidate
     // the state cached in skia so that the deferred copy on write
     // in SkSurface_Gpu does not make any false assumptions.