Treat calls to CanvasRenderingContext2D.clearRect as operations that clear the canvas

Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 2095 matching lines @@
     // Set <1 page scale so that the clip rect should be larger than
     // the viewport size as passed into resize().
     webViewHelper.webView()->setPageScaleFactor(0.5);
 
     SkBitmap bitmap;
     ASSERT_TRUE(bitmap.allocN32Pixels(200, 200));
     bitmap.eraseColor(0);
     SkCanvas canvas(bitmap);
 
     blink::GraphicsContext context(&canvas);
-    context.setTrackOpaqueRegion(true);
+    context.setRegionTrackingMode(GraphicsContext::RegionTrackingOpaque);
 
     EXPECT_EQ_RECT(blink::IntRect(0, 0, 0, 0), context.opaqueRegion().asRect());
 
     blink::FrameView* view = webViewHelper.webViewImpl()->mainFrameImpl()->frameView();
     blink::IntRect paintRect(0, 0, 200, 200);
     view->paint(&context, paintRect);
 
     // FIXME: This test broke in release builds when changing the FixedLayoutTestWebViewClient
     // to return a non-null layerTreeView, which is what all our shipping configurations do,
     // so this is just exposing an existing bug.
@@ skipping 3795 matching lines @@
 
     client.reset();
     // Try to load the request with cross origin access. Should succeed.
     options.crossOriginRequestPolicy = blink::AllowCrossOriginRequests;
     blink::DocumentThreadableLoader::loadResourceSynchronously(
         *frame->document(), blink::ResourceRequest(resourceUrl), client, options, resourceLoaderOptions);
     EXPECT_FALSE(client.failed());
 }
 
 } // namespace