Fix RenderFrameHost lifetime and clean up CommitPending.

content/browser/frame_host/render_frame_host_impl.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_IMPL_H_
 #define CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_IMPL_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 57 matching lines @@
     : public RenderFrameHost,
       public BrowserAccessibilityDelegate {
  public:
   // Keeps track of the state of the RenderFrameHostImpl, particularly with
   // respect to swap out.
   enum RenderFrameHostImplState {
     // The standard state for a RFH handling the communication with an active
     // RenderFrame.
     STATE_DEFAULT = 0,
     // The RFH has not received the SwapOutACK yet, but the new page has
-    // committed in a different RFH. The number of active frames of the RFH
-    // SiteInstanceImpl is not zero. Upon reception of the SwapOutACK, the RFH
-    // will be swapped out.
+    // committed in a different RFH.  Upon reception of the SwapOutACK, the RFH
+    // will either enter STATE_SWAPPED_OUT (if it is a main frame and there are
+    // other active frames in its SiteInstance) or it will be deleted.
     STATE_PENDING_SWAP_OUT,
-    // The RFH has not received the SwapOutACK yet, but the new page has
-    // committed in a different RFH. The number of active frames of the RFH
-    // SiteInstanceImpl is zero. Upon reception of the SwapOutACK, the RFH will
-    // be shutdown.
-    STATE_PENDING_SHUTDOWN,
     // The RFH is swapped out and stored inside a RenderFrameProxyHost, being
-    // used as a placeholder to allow cross-process communication.
+    // used as a placeholder to allow cross-process communication.  Only main
+    // frames can enter this state.
     STATE_SWAPPED_OUT,
   };
   // Helper function to determine whether the RFH state should contribute to the
   // number of active frames of a SiteInstance or not.
   static bool IsRFHStateActive(RenderFrameHostImplState rfh_state);
 
   static RenderFrameHostImpl* FromID(int process_id, int routing_id);
 
   virtual ~RenderFrameHostImpl();
 
@@ skipping 108 matching lines @@
       ui::PageTransition page_transition,
       bool should_replace_current_entry);
 
   // Called on the current RenderFrameHost when the network response is first
   // receieved.
   void OnDeferredAfterResponseStarted(
       const GlobalRequestID& global_request_id,
       const TransitionLayerData& transition_data);
 
   // Tells the renderer that this RenderFrame is being swapped out for one in a
-  // different renderer process.  It should run its unload handler, move to
-  // a blank document and create a RenderFrameProxy to replace the RenderFrame.
-  // The renderer should preserve the Proxy object until it exits, in case we
-  // come back.  The renderer can exit if it has no other active RenderFrames,
-  // but not until WasSwappedOut is called (when it is no longer visible).
+  // different renderer process.  It should run its unload handler and move to
+  // a blank document.  If |proxy| is not null, it should also create a
+  // RenderFrameProxy to replace the RenderFrame. The renderer should preserve
+  // the RenderFrameProxy object until it exits, in case we come back.  The
+  // renderer can exit if it has no other active RenderFrames, but not until
+  // WasSwappedOut is called.
   void SwapOut(RenderFrameProxyHost* proxy);
 
   bool is_waiting_for_beforeunload_ack() const {
     return is_waiting_for_beforeunload_ack_;
   }
 
   // Whether the RFH is waiting for an unload ACK from the renderer.
   bool IsWaitingForUnloadACK() const;
 
   // Called when either the SwapOut request has been acknowledged or has timed
   // out.
   void OnSwappedOut();
 
   // Whether this RenderFrameHost has been swapped out, such that the frame is
   // now rendered by a RenderFrameHost in a different process.
   bool is_swapped_out() const { return rfh_state_ == STATE_SWAPPED_OUT; }
 
   // The current state of this RFH.
   RenderFrameHostImplState rfh_state() const { return rfh_state_; }
 
-  // Set |this| as pending shutdown. |on_swap_out| will be called
-  // when the SwapOutACK is received, or when the unload timer times out.
-  void SetPendingShutdown(const base::Closure& on_swap_out);
-
   // Sends the given navigation message. Use this rather than sending it
   // yourself since this does the internal bookkeeping described below. This
   // function takes ownership of the provided message pointer.
   //
   // If a cross-site request is in progress, we may be suspended while waiting
   // for the onbeforeunload handler, so this function might buffer the message
   // rather than sending it.
   void Navigate(const FrameMsg_Navigate_Params& params);
 
   // Load the specified URL; this is a shortcut for Navigate().
@@ skipping 289 matching lines @@
   // IsWaitingForUnloadACK is true.  This tells us if the unload request
   // is for closing the entire tab ( = false), or only this RenderFrameHost in
   // the case of a cross-site transition ( = true).
   bool unload_ack_is_for_cross_site_transition_;
 
   // Used to swap out or shut down this RFH when the unload event is taking too
   // long to execute, depending on the number of active frames in the
   // SiteInstance.
   scoped_ptr<TimeoutMonitor> swapout_event_monitor_timeout_;
 
-  // Called after receiving the SwapOutACK when the RFH is in the pending
-  // shutdown state. Also called if the unload timer times out.
-  base::Closure pending_shutdown_on_swap_out_;
-
   ServiceRegistryImpl service_registry_;
 
   scoped_ptr<BrowserAccessibilityManager> browser_accessibility_manager_;
 
   // Callback when an event is received, for testing.
   base::Callback<void(ui::AXEvent, int)> accessibility_testing_callback_;
   // The most recently received accessibility tree - for testing only.
   scoped_ptr<ui::AXTree> ax_tree_for_testing_;
 
   // NOTE: This must be the last member.
   base::WeakPtrFactory<RenderFrameHostImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderFrameHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_IMPL_H_