Avoid exiting the renderer process if it has a pending render view.

content/browser/renderer_host/browser_render_process_host.h

 // Copyright (c) 2011 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_RENDERER_HOST_BROWSER_RENDER_PROCESS_HOST_H_
 #define CONTENT_BROWSER_RENDERER_HOST_BROWSER_RENDER_PROCESS_HOST_H_
 #pragma once
 
 #include <map>
 #include <queue>
@@ skipping 40 matching lines @@
   virtual int GetNextRoutingID();
   virtual void CancelResourceRequests(int render_widget_id);
   virtual void CrossSiteClosePageACK(const ViewMsg_ClosePage_Params& params);
   virtual bool WaitForUpdateMsg(int render_widget_id,
                                 const base::TimeDelta& max_delay,
                                 IPC::Message* msg);
   virtual void ReceivedBadMessage();
   virtual void WidgetRestored();
   virtual void WidgetHidden();
   virtual int VisibleWidgetCount() const;
+  virtual void AddPendingView();
+  virtual void RemovePendingView();
+  virtual int PendingViewCount() const;

[jam, 2011/05/06 17:45:11]

I don't see this being used anywhere?

[Charlie Reis, 2011/05/10 00:57:03]

Done.

   virtual bool FastShutdownIfPossible();
   virtual bool SendWithTimeout(IPC::Message* msg, int timeout_ms);
   virtual base::ProcessHandle GetHandle();
   virtual TransportDIB* GetTransportDIB(TransportDIB::Id dib_id);
 
   // IPC::Channel::Sender via RenderProcessHost.
   virtual bool Send(IPC::Message* msg);
 
   // IPC::Channel::Listener via RenderProcessHost.
   virtual bool OnMessageReceived(const IPC::Message& msg);
   virtual void OnChannelConnected(int32 peer_pid);
   virtual void OnChannelError();
 
   // ChildProcessLauncher::Client implementation.
   virtual void OnProcessLaunched();
 
  private:
   friend class VisitRelayingRenderProcessHost;
 
   // Creates and adds the IO thread message filters.
   void CreateMessageFilters();
 
   // Control message handlers.
+  void OnShutdownRequest();
   void OnUpdatedCacheStats(const WebKit::WebCache::UsageStats& stats);
   void SuddenTerminationChanged(bool enabled);
   void OnUserMetricsRecordAction(const std::string& action);
 
   // Generates a command line to be used to spawn a renderer and appends the
   // results to |*command_line|.
   void AppendRendererCommandLine(CommandLine* command_line) const;
 
   // Copies applicable command line switches from the given |browser_cmd| line
   // flags to the output |renderer_cmd| line flags. Not all switches will be
   // copied over.
   void PropagateBrowserCommandLineToRenderer(const CommandLine& browser_cmd,
                                              CommandLine* renderer_cmd) const;
 
   // Callers can reduce the RenderProcess' priority.
   void SetBackgrounded(bool backgrounded);
 
   // The count of currently visible widgets.  Since the host can be a container
   // for multiple widgets, it uses this count to determine when it should be
   // backgrounded.
   int32 visible_widgets_;
 
+  // The count of currently swapped out but pending RenderViews.  We have
+  // started to swap these back in, so the renderer process should not exit if
+  // this count is non-zero.
+  int32 pending_views_;
+
   // Does this process have backgrounded priority.
   bool backgrounded_;
 
   // Used to allow a RenderWidgetHost to intercept various messages on the
   // IO thread.
   scoped_refptr<RenderWidgetHelper> widget_helper_;
 
   // A map of transport DIB ids to cached TransportDIBs
   std::map<TransportDIB::Id, TransportDIB*> cached_dibs_;
   enum {
@@ skipping 24 matching lines @@
   // Messages we queue while waiting for the process handle.  We queue them here
   // instead of in the channel so that we ensure they're sent after init related
   // messages that are sent once the process handle is available.  This is
   // because the queued messages may have dependencies on the init messages.
   std::queue<IPC::Message*> queued_messages_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserRenderProcessHost);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_BROWSER_RENDER_PROCESS_HOST_H_