Fix a bug where we'd leak ResourceMessageFilters and BrowserRenderProcessHosts

chrome/browser/extensions/extension_process_manager.cc

 // Copyright (c) 2009 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 "chrome/browser/extensions/extension_process_manager.h"
 
 #include "chrome/browser/browsing_instance.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extensions_service.h"
 #include "chrome/browser/profile.h"
@@ skipping 26 matching lines @@
   registrar_.Add(this, NotificationType::EXTENSION_LOADED,
                  NotificationService::AllSources());
   registrar_.Add(this, NotificationType::EXTENSION_UNLOADED,
                  NotificationService::AllSources());
   registrar_.Add(this, NotificationType::EXTENSION_HOST_DESTROYED,
                  Source<Profile>(profile));
   registrar_.Add(this, NotificationType::RENDERER_PROCESS_TERMINATED,
                  NotificationService::AllSources());
   registrar_.Add(this, NotificationType::RENDERER_PROCESS_CLOSED,
                  NotificationService::AllSources());
+  registrar_.Add(this, NotificationType::BROWSER_CLOSED,
+                 NotificationService::AllSources());
 }
 
 ExtensionProcessManager::~ExtensionProcessManager() {
-  // Copy all_hosts_ to avoid iterator invalidation issues.
-  ExtensionHostSet to_delete(background_hosts_.begin(),
-                             background_hosts_.end());
-  ExtensionHostSet::iterator iter;
-  for (iter = to_delete.begin(); iter != to_delete.end(); ++iter)
-    delete *iter;
+  DCHECK(background_hosts_.empty());
 }
 
 ExtensionHost* ExtensionProcessManager::CreateView(Extension* extension,
                                                    const GURL& url,
                                                    Browser* browser,
                                                    ViewType::Type view_type) {
   DCHECK(extension);
   DCHECK(browser);
   ExtensionHost* host =
       new ExtensionHost(extension, GetSiteInstanceForURL(url), url, view_type);
@@ skipping 144 matching lines @@
       break;
     }
 
     case NotificationType::RENDERER_PROCESS_TERMINATED:
     case NotificationType::RENDERER_PROCESS_CLOSED: {
       RenderProcessHost* host = Source<RenderProcessHost>(source).ptr();
       UnregisterExtensionProcess(host->id());
       break;
     }
 
+    case NotificationType::BROWSER_CLOSED: {
+      // Close background hosts when the last browser is closed so that they
+      // have time to shutdown various objects on different threads. Our
+      // destructor is called too late in the shutdown sequence.
+      bool app_closing = *Details<bool>(details).ptr();
+      if (app_closing)
+        CloseBackgroundHosts();
+      break;
+    }
+
     default:
       NOTREACHED();
   }
 }
 
 void ExtensionProcessManager::OnExtensionHostCreated(ExtensionHost* host,
                                                      bool is_background) {
   all_hosts_.insert(host);
   if (is_background)
     background_hosts_.insert(host);
   NotificationService::current()->Notify(
       NotificationType::EXTENSION_HOST_CREATED,
       Source<ExtensionProcessManager>(this),
       Details<ExtensionHost>(host));
 }
+
+void ExtensionProcessManager::CloseBackgroundHosts() {
+  for (ExtensionHostSet::iterator iter = background_hosts_.begin();
+       iter != background_hosts_.end(); ) {
+    ExtensionHostSet::iterator current = iter++;
+    delete *current;
+  }
+}