Refactor DrawingRecorders to check for cached drawings earlier

Source/web/WebGraphicsContextImpl.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "web/WebGraphicsContextImpl.h"
 
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/paint/DrawingRecorder.h"
 
@@ skipping 12 matching lines @@
 WebGraphicsContextImpl::~WebGraphicsContextImpl()
 {
 }
 
 WebCanvas* WebGraphicsContextImpl::beginDrawing(const WebFloatRect& bounds)
 {
 #ifndef NDEBUG
     ASSERT(!m_hasBegunDrawing);
     m_hasBegunDrawing = true;
 #endif
+    ASSERT(!DrawingRecorder::useCachedDrawingIfPossible(m_graphicsContext, m_client, m_type));
     m_drawingRecorder = adoptPtr(new DrawingRecorder(m_graphicsContext, m_client, m_type, bounds));
-
-    ASSERT(!m_drawingRecorder->canUseCachedDrawing());
-
     WebCanvas* canvas = m_graphicsContext.canvas();
     ASSERT(canvas);
     return canvas;
 }
 
 void WebGraphicsContextImpl::endDrawing()
 {
     ASSERT(m_drawingRecorder);
     m_drawingRecorder.clear();
 }
 
 } // namespace blink