Get rid of a dependency on MessageLoop::DestructionObserver....

webkit/tools/test_shell/simple_appcache_system.h

Index: webkit/tools/test_shell/simple_appcache_system.h
===================================================================
--- webkit/tools/test_shell/simple_appcache_system.h	(revision 65856)
+++ webkit/tools/test_shell/simple_appcache_system.h	(working copy)
@@ -28,7 +28,7 @@
 // a UI thread on which webkit runs and an IO thread on which URLRequests
 // are handled. This class conspires with SimpleResourceLoaderBridge to
 // retrieve resources from the appcache.
-class SimpleAppCacheSystem : public MessageLoop::DestructionObserver {
+class SimpleAppCacheSystem {
  public:
   // Should be instanced somewhere in main(). If not instanced, the public
   // static methods are all safe no-ops.
@@ -51,6 +51,11 @@
       instance_->InitOnIOThread(request_context);
   }
 
+  static void CleanupOnIOThread() {
+    if (instance_)
+      instance_->CleanupIOThread();
+  }
+
   // Called by TestShellWebKitInit to manufacture a 'host' for webcore.
   static WebKit::WebApplicationCacheHost* CreateApplicationCacheHost(
       WebKit::WebApplicationCacheHostClient* client) {
@@ -108,6 +113,7 @@
   // Instance methods called by our static public methods
   void InitOnUIThread(const FilePath& cache_directory);
   void InitOnIOThread(URLRequestContext* request_context);
+  void CleanupIOThread();
   WebKit::WebApplicationCacheHost* CreateCacheHostForWebKit(
       WebKit::WebApplicationCacheHostClient* client);
   void SetExtraRequestBits(URLRequest* request,
@@ -139,9 +145,6 @@
     return NULL;
   }
 
-  // IOThread DestructionObserver
-  virtual void WillDestroyCurrentMessageLoop();
-
   FilePath cache_directory_;
   MessageLoop* io_message_loop_;
   MessageLoop* ui_message_loop_;