Minor clean up in transferToImageBitmap API

third_party/WebKit/Source/core/html/canvas/CanvasRenderingContext.h

Index: third_party/WebKit/Source/core/html/canvas/CanvasRenderingContext.h
diff --git a/third_party/WebKit/Source/core/html/canvas/CanvasRenderingContext.h b/third_party/WebKit/Source/core/html/canvas/CanvasRenderingContext.h
index ce8c3fc7cdce39f19d98471195da2302ab41f4b2..79035573d20abb9965a679b7755aecf0dd2474a3 100644
--- a/third_party/WebKit/Source/core/html/canvas/CanvasRenderingContext.h
+++ b/third_party/WebKit/Source/core/html/canvas/CanvasRenderingContext.h
@@ -162,9 +162,7 @@ class CORE_EXPORT CanvasRenderingContext
 
   // OffscreenCanvas-specific methods
   OffscreenCanvas* getOffscreenCanvas() const { return m_offscreenCanvas; }
-  virtual ImageBitmap* transferToImageBitmap(ExceptionState&) {
-    return nullptr;
-  }
+  virtual ImageBitmap* transferToImageBitmap() { return nullptr; }
 
   bool wouldTaintOrigin(CanvasImageSource*, SecurityOrigin* = nullptr);
   void didMoveToNewDocument(Document*);