Fixed expando-loss.html test.

third_party/WebKit/Source/core/html/HTMLCanvasElement.h

 /*
  * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. 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.
@@ skipping 92 matching lines @@
         m_ignoreReset = true;
         setWidth(newSize.width());
         setHeight(newSize.height());
         m_ignoreReset = false;
         reset();
     }
 
     // Called by HTMLCanvasElement's V8 bindings.
     ScriptValue getContext(ScriptState*, const String&, const CanvasContextCreationAttributes&);
     // Called by Document::getCSSCanvasContext as well as above getContext().
-    CanvasRenderingContext* getCanvasRenderingContext(const String&, const CanvasContextCreationAttributes&);
+    // The WebGLRenderingContext requires a non-null ScriptState, but the Canvas2DRenderingContext does not.

[haraken, 2015/10/13 02:02:04]

In general, it is not nice to pass a nullptr to ScriptState. If this is a
testing-only issue, you can use V8TestingScope which gives you a ScriptState to
use.

+    CanvasRenderingContext* getCanvasRenderingContext(ScriptState*, const String&, const CanvasContextCreationAttributes&);
 
     bool isPaintable() const;
 
     static String toEncodingMimeType(const String& mimeType);
     String toDataURL(const String& mimeType, const ScriptValue& qualityArgument, ExceptionState&) const;
     String toDataURL(const String& mimeType, ExceptionState& exceptionState) const { return toDataURL(mimeType, ScriptValue(), exceptionState); }
 
     void toBlob(FileCallback*, const String& mimeType, const ScriptValue& qualityArgument, ExceptionState&);
     void toBlob(FileCallback* callback, const String& mimeType, ExceptionState& exceptionState) { return toBlob(callback, mimeType, ScriptValue(), exceptionState); }
 
@@ skipping 115 matching lines @@
     mutable bool m_didFailToCreateImageBuffer;
     bool m_imageBufferIsClear;
     OwnPtr<ImageBuffer> m_imageBuffer;
 
     mutable RefPtr<Image> m_copiedImage; // FIXME: This is temporary for platforms that have to copy the image buffer to render (and for CSSCanvasValue).
 };
 
 } // namespace blink
 
 #endif // HTMLCanvasElement_h