Eliminated the last few uses of MessageLoop::QuitTask in chrome/

chrome/test/base/testing_profile.cc

Index: chrome/test/base/testing_profile.cc
diff --git a/chrome/test/base/testing_profile.cc b/chrome/test/base/testing_profile.cc
index 008c87128cff4443eb40b9b151e0ce337f21217e..6a96762814923f433e440ee48ffa9659b441509a 100644
--- a/chrome/test/base/testing_profile.cc
+++ b/chrome/test/base/testing_profile.cc
@@ -259,7 +259,7 @@ void TestingProfile::DestroyHistoryService() {
     return;
 
   history_service_->NotifyRenderProcessHostDestruction(0);
-  history_service_->SetOnBackendDestroyTask(new MessageLoop::QuitTask);
+  history_service_->SetOnBackendDestroyTask(MessageLoop::QuitClosure());
   history_service_->Cleanup();
   history_service_ = NULL;
 
@@ -271,7 +271,7 @@ void TestingProfile::DestroyHistoryService() {
 
   // Make sure we don't have any event pending that could disrupt the next
   // test.
-  MessageLoop::current()->PostTask(FROM_HERE, new MessageLoop::QuitTask);
+  MessageLoop::current()->PostTask(FROM_HERE, MessageLoop::QuitClosure());
   MessageLoop::current()->Run();
 }