[Extensions] Propagate activeTab hosts to extension background pages

extensions/browser/process_manager.cc

 // 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.
 
 #include "extensions/browser/process_manager.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
@@ skipping 360 matching lines @@
     if (host->extension_id() == extension_id)
       return host;
   }
   return NULL;
 }
 
 std::set<RenderViewHost*> ProcessManager::GetRenderViewHostsForExtension(
     const std::string& extension_id) {
   std::set<RenderViewHost*> result;
 
-  SiteInstance* site_instance = GetSiteInstanceForURL(
-      Extension::GetBaseURLFromExtensionId(extension_id));
-  if (!site_instance)
+  scoped_refptr<SiteInstance> site_instance(GetSiteInstanceForURL(
+      Extension::GetBaseURLFromExtensionId(extension_id)));
+  if (!site_instance.get())
     return result;
 
   // Gather up all the views for that site.
   for (ExtensionRenderViews::iterator view = all_extension_views_.begin();
        view != all_extension_views_.end(); ++view) {
     if (view->first->GetSiteInstance() == site_instance)
       result.insert(view->first);
   }
 
   return result;
@@ skipping 639 matching lines @@
   if (extension && !IncognitoInfo::IsSplitMode(extension)) {
     BrowserContext* original_context =
         ExtensionsBrowserClient::Get()->GetOriginalContext(GetBrowserContext());
     return ProcessManager::Get(original_context)->GetSiteInstanceForURL(url);
   }
 
   return ProcessManager::GetSiteInstanceForURL(url);
 }
 
 }  // namespace extensions