Mark WebGLRenderingContext as having lost context upon init failure.

Source/core/html/canvas/WebGLRenderingContextBase.cpp

 /*
  * Copyright (C) 2009 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 627 matching lines @@
 {
     ASSERT(context);
 
     m_contextGroup = WebGLContextGroup::create();
     m_contextGroup->addContext(this);
 
     m_maxViewportDims[0] = m_maxViewportDims[1] = 0;
     context->getIntegerv(GL_MAX_VIEWPORT_DIMS, m_maxViewportDims);
 
     RefPtr<DrawingBuffer> buffer = createDrawingBuffer(context);
-    if (!buffer)
+    if (!buffer) {
+        m_contextLostMode = SyntheticLostContext;
         return;
+    }
 
 #if ENABLE(OILPAN)
     m_sharedWebGraphicsContext3D = WebGLSharedWebGraphicsContext3D::create(buffer.release());
 #else
     m_drawingBuffer = buffer.release();
 #endif
 
     drawingBuffer()->bind();
     setupFlags();
 }
@@ skipping 5580 matching lines @@
     return m_sharedWebGraphicsContext3D ? m_sharedWebGraphicsContext3D->drawingBuffer() : 0;
 }
 #else
 DrawingBuffer* WebGLRenderingContextBase::drawingBuffer() const
 {
     return m_drawingBuffer.get();
 }
 #endif
 
 } // namespace blink