Move GetDocument method from WebFrame to WebLocalFrame.

third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.cpp

Index: third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.cpp
diff --git a/third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.cpp b/third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.cpp
index 99a9749b2add76f5926c24bb515e84c075535965..dd64d7bffa6ebc2d69d80d057fa716f7eab62841 100644
--- a/third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.cpp
+++ b/third_party/WebKit/Source/core/exported/WebRemoteFrameImpl.cpp
@@ -132,12 +132,6 @@ WebView* WebRemoteFrameImpl::View() const {
   return GetFrame()->GetPage()->GetChromeClient().GetWebView();
 }
 
-WebDocument WebRemoteFrameImpl::GetDocument() const {
-  // TODO(dcheng): this should also ASSERT_NOT_REACHED, but a lot of
-  // code tries to access the document of a remote frame at the moment.
-  return WebDocument();
-}
-
 WebPerformance WebRemoteFrameImpl::Performance() const {
   NOTREACHED();
   return WebPerformance();