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

content/browser/renderer_host/render_process_host.h

Index: content/browser/renderer_host/render_process_host.h
diff --git a/content/browser/renderer_host/render_process_host.h b/content/browser/renderer_host/render_process_host.h
index b38402658e297a0061e09cfe23dec2f20da1c73a..ee6c7ed6420502a924a0144eb23c2e57d4f3350b 100644
--- a/content/browser/renderer_host/render_process_host.h
+++ b/content/browser/renderer_host/render_process_host.h
@@ -190,6 +190,13 @@ class RenderProcessHost : public IPC::Channel::Sender,
   virtual void WidgetHidden() = 0;
   virtual int VisibleWidgetCount() const = 0;
 
+  // Track the count of pending views that are being swapped back in.  Called
+  // by listeners to register and unregister pending views to prevent the
+  // process from exiting.
+  virtual void AddPendingView() = 0;
+  virtual void RemovePendingView() = 0;
+  virtual int PendingViewCount() const = 0;
+
   // Try to shutdown the associated renderer process as fast as possible.
   // If this renderer has any RenderViews with unload handlers, then this
   // function does nothing.  The current implementation uses TerminateProcess.