If the renderer drops a navigation, make sure the spinner doesn't spin endlessly.

content/browser/frame_host/render_frame_host_delegate.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
 #define CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 39 matching lines @@
                                    const base::string16& message,
                                    int32 line_no,
                                    const base::string16& source_id);
 
   // Informs the delegate whenever a RenderFrameHost is created.
   virtual void RenderFrameCreated(RenderFrameHost* render_frame_host) {}
 
   // Informs the delegate whenever a RenderFrameHost is deleted.
   virtual void RenderFrameDeleted(RenderFrameHost* render_frame_host) {}
 
-  // The top-level RenderFrame began loading a new page. This corresponds to
+  // The specified RenderFrame began loading a new page. This corresponds to
   // Blink's notion of the throbber starting.
   // |to_different_document| will be true unless the load is a fragment
   // navigation, or triggered by history.pushState/replaceState.
   virtual void DidStartLoading(RenderFrameHost* render_frame_host,
                                bool to_different_document) {}
 
+  // The specified RenderFrame stopped loading a page. This corresponds to
+  // Blink's notion of the throbber stopping.
+  virtual void DidStopLoading(RenderFrameHost* render_frame_host) {}
+
   // The RenderFrameHost has been swapped out.
   virtual void SwappedOut(RenderFrameHost* render_frame_host) {}
 
   // Notification that the navigation on the main frame is blocked waiting
   // for transition to occur.
   virtual void DidDeferAfterResponseStarted(
       const TransitionLayerData& transition_data) {}
 
   // Used to query whether the navigation transition will be handled.
   virtual bool WillHandleDeferAfterResponseStarted();
@@ skipping 79 matching lines @@
   virtual gfx::NativeViewAccessible GetParentNativeViewAccessible();
 #endif
 
  protected:
   virtual ~RenderFrameHostDelegate() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_