Revert of Revert of Make start/stop loading notifications per-frame

public/web/WebViewClient.h

Index: public/web/WebViewClient.h
diff --git a/public/web/WebViewClient.h b/public/web/WebViewClient.h
index cb113b0873988d66d2ad657fbd1ce840e1513cd7..42e6f4691ff675d11db606909234876f480ee161 100644
--- a/public/web/WebViewClient.h
+++ b/public/web/WebViewClient.h
@@ -146,16 +146,6 @@
     // will never be called.
     virtual bool enumerateChosenDirectory(const WebString& path, WebFileChooserCompletion*) { return false; }
 
-    // Navigational --------------------------------------------------------
-
-    // These notifications bracket any loading that occurs in the WebView.
-    virtual void didStartLoading(bool toDifferentDocument) { }
-    virtual void didStopLoading() { }
-
-    // Notification that some progress was made loading the current page.
-    // loadProgress is a value between 0 (nothing loaded) and 1.0 (frame fully
-    // loaded).
-    virtual void didChangeLoadProgress(WebLocalFrame*, double loadProgress) { }
 
     // Editing -------------------------------------------------------------