Move MainWorldScriptContext accessor/method from WebFrame to WebLocalFrame.

extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.cc

Index: extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.cc
diff --git a/extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.cc b/extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.cc
index c27ded7fa9bb86d6cdbeab43c28935b32d30aca1..4c3b5f48cbf0f868f607c4abe1bc784d26e325a0 100644
--- a/extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.cc
+++ b/extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.cc
@@ -240,7 +240,9 @@ void MimeHandlerViewContainer::PostMessage(v8::Isolate* isolate,
   // on top of out-of-process iframes. Remove it once the code is converted.
   v8::Local<v8::Object> guest_proxy_window;
   if (guest_proxy_frame->IsWebLocalFrame()) {
-    guest_proxy_window = guest_proxy_frame->MainWorldScriptContext()->Global();
+    guest_proxy_window = guest_proxy_frame->ToWebLocalFrame()
+                             ->MainWorldScriptContext()
+                             ->Global();
   } else {
     guest_proxy_window = guest_proxy_frame->ToWebRemoteFrame()->GlobalProxy();

[dcheng, 2017/06/06 19:57:17]

Since it would be used here (and a couple other places) as well.

   }
@@ -261,7 +263,7 @@ void MimeHandlerViewContainer::PostMessage(v8::Isolate* isolate,
 
 void MimeHandlerViewContainer::PostMessageFromValue(
     const base::Value& message) {
-  blink::WebFrame* frame = render_frame()->GetWebFrame();
+  blink::WebLocalFrame* frame = render_frame()->GetWebFrame();
   if (!frame)
     return;
 
@@ -302,7 +304,7 @@ void MimeHandlerViewContainer::OnMimeHandlerViewGuestOnLoadCompleted(
     return;
 
   // Now that the guest has loaded, flush any unsent messages.
-  blink::WebFrame* frame = render_frame()->GetWebFrame();
+  blink::WebLocalFrame* frame = render_frame()->GetWebFrame();
   if (!frame)
     return;