Speculative fix for 2D canvas crash on Mac

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

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 584 matching lines @@
         // Using accelerated 2d canvas with software renderer, which
         // should only happen in tests that use fake graphics contexts
         // or in Android WebView in software mode. In this case, we do
         // not care about producing any results for this canvas.
         skipQueuedDrawCommands();
         m_lastImageId = 0;
         return false;
     }
 
     RefPtr<SkImage> image = newImageSnapshot(PreferAcceleration);
-    if (!image)
+    if (!image || !image->getTexture())
         return false;
 
     WebGraphicsContext3D* webContext = context();
 
     // Early exit if canvas was not drawn to since last prepareMailbox
     GLenum filter = m_filterQuality == kNone_SkFilterQuality ? GL_NEAREST : GL_LINEAR;
     if (image->uniqueID() == m_lastImageId && filter == m_lastFilter)
         return false;
     m_lastImageId = image->uniqueID();
     m_lastFilter = filter;
 
     {
         MailboxInfo tmp;
         tmp.m_image = image;
         tmp.m_parentLayerBridge = this;
         m_mailboxes.prepend(tmp);
     }
     MailboxInfo& mailboxInfo = m_mailboxes.first();
 
     mailboxInfo.m_mailbox.nearestNeighbor = filter == GL_NEAREST;
 
     GrContext* grContext = m_contextProvider->grContext();
     if (!grContext)
         return true; // for testing: skip gl stuff when using a mock graphics context.
 
     // 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.
     mailboxInfo.m_image->getTexture()->textureParamsModified();
     mailboxInfo.m_mailbox.textureTarget = GL_TEXTURE_2D;
 
     webContext->bindTexture(GL_TEXTURE_2D, mailboxInfo.m_image->getTexture()->getTextureHandle());
     webContext->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, filter);
     webContext->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, filter);
     webContext->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
@@ skipping 176 matching lines @@
     m_image = other.m_image;
     m_parentLayerBridge = other.m_parentLayerBridge;
 }
 
 void Canvas2DLayerBridge::Logger::reportHibernationEvent(HibernationEvent event)
 {
     blink::Platform::current()->histogramEnumeration("Canvas.HibernationEvents", event, HibernationEventCount);
 }
 
 } // namespace blink