Use document's contentSize when the HTML element is selected.

Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 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 849 matching lines @@
     // behaves as the editor but we want to return the actual element's bounds.
     // In practice, that means <textarea> and <input> controls that behave like
     // a text field.
     Element* shadowHost = root->shadowHost();
     if (shadowHost
         && (isHTMLTextAreaElement(*shadowHost)
             || (isHTMLInputElement(*shadowHost)
                 && toHTMLInputElement(*shadowHost).isText())))
         root = shadowHost;
 
-    IntRect boundingBox = root->pixelSnappedBoundingBox();
+    IntRect boundingBox = isHTMLHtmlElement(root)
+        ? IntRect(IntPoint(0, 0), root->document().frame()->view()->contentsSize())
+        : root->pixelSnappedBoundingBox();
+
     boundingBox = root->document().frame()->view()->contentsToWindow(boundingBox);
     boundingBox.scale(pageScaleFactor());
     bounds = boundingBox;
 }
 
 bool WebViewImpl::handleKeyEvent(const WebKeyboardEvent& event)
 {
     ASSERT((event.type == WebInputEvent::RawKeyDown)
         || (event.type == WebInputEvent::KeyDown)
         || (event.type == WebInputEvent::KeyUp));
@@ skipping 3127 matching lines @@
     const PageScaleConstraints& constraints = m_pageScaleConstraintsSet.pageDefinedConstraints();
 
     if (!mainFrameImpl() || !mainFrameImpl()->frameView())
         return false;
 
     return mainFrameImpl()->frameView()->layoutSize().width() == m_size.width
         || (constraints.minimumScale == constraints.maximumScale && constraints.minimumScale != -1);
 }
 
 } // namespace blink