Revert of Remove the is_loading_ field from WebContentsImpl

content/browser/web_contents/web_contents_impl.h

Index: content/browser/web_contents/web_contents_impl.h
diff --git a/content/browser/web_contents/web_contents_impl.h b/content/browser/web_contents/web_contents_impl.h
index 6fdc6877ac4a2e8bff4976ab9b4cabe6c6fd94ad..6a5ba60abdbc441433f57f9c6f5708978bcdd7a0 100644
--- a/content/browser/web_contents/web_contents_impl.h
+++ b/content/browser/web_contents/web_contents_impl.h
@@ -706,8 +706,12 @@
   // Unsets the currently showing interstitial.
   void DetachInterstitialPage() override;
 
-  // Unpause the throbber if it was paused.
-  void DidProceedOnInterstitial() override;
+  // Changes the IsLoading state and notifies the delegate as needed.
+  // |details| is used to provide details on the load that just finished
+  // (but can be null if not applicable).
+  void SetIsLoading(bool is_loading,
+                    bool to_different_document,
+                    LoadNotificationDetails* details) override;
 
   typedef base::Callback<void(WebContents*)> CreatedCallback;
 
@@ -1012,16 +1016,6 @@
   // the main frame if empty).
   WebUI* CreateWebUI(const GURL& url, const std::string& frame_name);
 
-  // Notifies the delegate of a change in loading state.
-  // |details| is used to provide details on the load that just finished
-  // (but can be null if not applicable).
-  // |pause_throbber_for_interstitial_| will be used to update
-  // pause_throbber_for_interstitial_.
-  void LoadingStateChanged(bool is_loading,
-                           bool to_different_document,
-                           bool pause_throbber_for_interstitial,
-                           LoadNotificationDetails* details);
-
   // Data for core operation ---------------------------------------------------
 
   // Delegate for notifying our owner about stuff. Not owned by us.
@@ -1079,6 +1073,9 @@
 
   // Data for loading state ----------------------------------------------------
 
+  // Indicates whether we're currently loading a resource.
+  bool is_loading_;
+
   // Indicates whether the current load is to a different document. Only valid
   // if is_loading_ is true.
   bool is_load_to_different_document_;
@@ -1111,10 +1108,6 @@
   // Tracks that this WebContents needs to unblock requests to the renderer.
   // See ResumeLoadingCreatedWebContents.
   bool is_resume_pending_;
-
-  // Whether the throbber is suspended while an interstial page is showing.
-  // This is set to false when the user proceeds in the interstitial.
-  bool paused_throbber_for_interstitial_;
 
   // Data for current page -----------------------------------------------------