Clear pending events for transient pages when it crashes.

chrome/browser/extensions/lazy_background_task_queue.cc

 // 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.
 
 #include "chrome/browser/extensions/lazy_background_task_queue.h"
 
 #include "base/callback.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ skipping 11 matching lines @@
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/site_instance.h"
 #include "content/public/browser/web_contents.h"
 
 namespace extensions {
 
 LazyBackgroundTaskQueue::LazyBackgroundTaskQueue(Profile* profile)
     : profile_(profile) {
   registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_HOST_DID_STOP_LOADING,
                  content::NotificationService::AllBrowserContextsAndSources());
+  registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_HOST_DESTROYED,
+                 content::NotificationService::AllBrowserContextsAndSources());
   registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_UNLOADED,
                  content::Source<Profile>(profile));
 }
 
 LazyBackgroundTaskQueue::~LazyBackgroundTaskQueue() {
 }
 
 bool LazyBackgroundTaskQueue::ShouldEnqueueTask(
     Profile* profile, const Extension* extension) {
   DCHECK(extension);
@@ skipping 17 matching lines @@
   PendingTasksMap::iterator it = pending_tasks_.find(key);
   if (it == pending_tasks_.end()) {
     tasks_list = new PendingTasksList();
     pending_tasks_[key] = linked_ptr<PendingTasksList>(tasks_list);
 
     // If this is the first enqueued task, ensure the background page
     // is loaded.
     const Extension* extension = profile->GetExtensionService()->
         extensions()->GetByID(extension_id);
     DCHECK(extension->has_lazy_background_page());
-  ExtensionProcessManager* pm = profile->GetExtensionProcessManager();
+    ExtensionProcessManager* pm = profile->GetExtensionProcessManager();
     pm->IncrementLazyKeepaliveCount(extension);
     pm->CreateBackgroundHost(extension, extension->GetBackgroundURL());
   } else {
     tasks_list = it->second.get();
   }
 
   tasks_list->push_back(task);
 }
 
 void LazyBackgroundTaskQueue::ProcessPendingTasks(ExtensionHost* host) {
@@ skipping 29 matching lines @@
       ExtensionHost* host = content::Details<ExtensionHost>(details).ptr();
       if (host->profile()->IsSameProfile(profile_) &&
           host->extension_host_type() ==
               chrome::VIEW_TYPE_EXTENSION_BACKGROUND_PAGE &&
           host->extension()->has_lazy_background_page()) {
         CHECK(host->did_stop_loading());
         ProcessPendingTasks(host);
       }
       break;
     }
+    case chrome::NOTIFICATION_EXTENSION_HOST_DESTROYED: {
+      // Clear pending tasks when the background host dies. This can happen
+      // if the extension crashes. This is not strictly necessary, since we
+      // also unload the extension in that case (which clears the tasks below),
+      // but is a good extra precaution.
+      Profile* profile = content::Source<Profile>(source).ptr();
+      ExtensionHost* host = content::Details<ExtensionHost>(details).ptr();
+      if (host->extension_host_type() ==
+              chrome::VIEW_TYPE_EXTENSION_BACKGROUND_PAGE) {
+        pending_tasks_.erase(PendingTasksKey(profile, host->extension()->id()));
+      }
+      break;
+    }
     case chrome::NOTIFICATION_EXTENSION_UNLOADED: {
       // Clear pending tasks for this extension.
       Profile* profile = content::Source<Profile>(source).ptr();
       UnloadedExtensionInfo* unloaded =
           content::Details<UnloadedExtensionInfo>(details).ptr();
       pending_tasks_.erase(PendingTasksKey(
           profile, unloaded->extension->id()));
       if (profile->HasOffTheRecordProfile())
         pending_tasks_.erase(PendingTasksKey(
             profile->GetOffTheRecordProfile(), unloaded->extension->id()));
       break;
     }
     default:
       NOTREACHED();
       break;
   }
 }
 
 }  // namespace extensions