Check BrowsingInstance before swapping prerenders.

content/browser/site_instance_impl.h

 // Copyright (c) 2012 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_SITE_INSTANCE_IMPL_H_
 #define CONTENT_BROWSER_SITE_INSTANCE_IMPL_H_
 
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/render_process_host_observer.h"
 #include "content/public/browser/site_instance.h"
 #include "url/gurl.h"
 
 namespace content {
+class BrowsingInstance;
 class RenderProcessHostFactory;
 
 class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
                                         public RenderProcessHostObserver {
  public:
   // SiteInstance interface overrides.
   virtual int32 GetId() OVERRIDE;
   virtual bool HasProcess() const OVERRIDE;
   virtual RenderProcessHost* GetProcess() OVERRIDE;
+  virtual BrowserContext* GetBrowserContext() const OVERRIDE;
   virtual const GURL& GetSiteURL() const OVERRIDE;
   virtual SiteInstance* GetRelatedSiteInstance(const GURL& url) OVERRIDE;
   virtual bool IsRelatedSiteInstance(const SiteInstance* instance) OVERRIDE;
-  virtual BrowserContext* GetBrowserContext() const OVERRIDE;
+  virtual size_t GetRelatedActiveContentsCount() OVERRIDE;
 
   // Set the web site that this SiteInstance is rendering pages for.
   // This includes the scheme and registered domain, but not the port.  If the
   // URL does not have a valid registered domain, then the full hostname is
   // stored.
   void SetSite(const GURL& url);
   bool HasSite() const;
 
   // Returns whether there is currently a related SiteInstance (registered with
   // BrowsingInstance) for the site of the given url.  If so, we should try to
@@ skipping 14 matching lines @@
   // decreased when a view is destroyed, or a currently active view is
   // swapped out.
   void decrement_active_view_count() { active_view_count_--; }
 
   // Get the number of active views which belong to this
   // SiteInstance. If there is no active view left in this
   // SiteInstance, all view in this SiteInstance can be safely
   // discarded to save memory.
   size_t active_view_count() { return active_view_count_; }
 
+  // Increase the number of active WebContentses using this SiteInstance. Note
+  // that, unlike active_view_count, this does not count pending RVHs.
+  void IncrementRelatedActiveContentsCount();
+
+  // Decrease the number of active WebContentses using this SiteInstance. Note
+  // that, unlike active_view_count, this does not count pending RVHs.
+  void DecrementRelatedActiveContentsCount();
+
   // Sets the global factory used to create new RenderProcessHosts.  It may be
   // NULL, in which case the default BrowserRenderProcessHost will be created
   // (this is the behavior if you don't call this function).  The factory must
   // be set back to NULL before it's destroyed; ownership is not transferred.
   static void set_render_process_host_factory(
       const RenderProcessHostFactory* rph_factory);
 
   // Get the effective URL for the given actual URL.  This allows the
   // ContentBrowserClient to override the SiteInstance's site for certain URLs.
   // For example, Chrome uses this to replace hosted app URLs with extension
@@ skipping 48 matching lines @@
 
   // Whether SetSite has been called.
   bool has_site_;
 
   DISALLOW_COPY_AND_ASSIGN(SiteInstanceImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SITE_INSTANCE_IMPL_H_