Convert remaining WebContentsObservers loading callbacks to use RFH.

chrome/browser/guest_view/web_view/web_view_guest.h

Index: chrome/browser/guest_view/web_view/web_view_guest.h
diff --git a/chrome/browser/guest_view/web_view/web_view_guest.h b/chrome/browser/guest_view/web_view/web_view_guest.h
index b79f9ef6f6be740e403cf473a2050f515ca66d80..447d06246c38463d532de0d65dc76d10303573bb 100644
--- a/chrome/browser/guest_view/web_view/web_view_guest.h
+++ b/chrome/browser/guest_view/web_view/web_view_guest.h
@@ -359,8 +359,7 @@ class WebViewGuest : public GuestView<WebViewGuest>,
       bool is_error_page,
       bool is_iframe_srcdoc) OVERRIDE;
   virtual void DocumentLoadedInFrame(
-      int64 frame_id,
-      content::RenderViewHost* render_view_host) OVERRIDE;
+      content::RenderFrameHost* render_frame_host) OVERRIDE;
   virtual bool OnMessageReceived(
       const IPC::Message& message,
       content::RenderFrameHost* render_frame_host) OVERRIDE;
@@ -450,9 +449,6 @@ class WebViewGuest : public GuestView<WebViewGuest>,
   // True if the user agent is overridden.
   bool is_overriding_user_agent_;
 
-  // Main frame ID of last committed page.
-  int64 main_frame_id_;
-
   // Set to |true| if ChromeVox was already injected in main frame.
   bool chromevox_injected_;