Revert 272998 "Revert 241291 "Fix a long standing leak on cancel..."

> Revert 241291 "Fix a long standing leak on cancellation of rende..."
> 
> This caused crashes elsewhere in the loading code.
> 
> BUG=27911
> 
> > Fix a long standing leak on cancellation of renderer-
> > initiated URLRequests.  ResourceDispatcher was not calling
> > peer->OnCompletedRequest on cancellation of async requests,
> > despite it being expected by WebURLLoaderImpl::Context
> > (The only ResourceLoaderBridge::Peer).
> > 
> > This shouldn't impact externally visible behavior at all,
> > other than fixing the leak, because once
> > WebURLLoaderImpl::Context::Cancel() is called, it will never
> > call back into WebURLLoaderImpl.
> > 
> > BUG=328092
> > 
> > Review URL: https://codereview.chromium.org/113893007
> 
> TBR=mmenke@chromium.org
> 
> Review URL: https://codereview.chromium.org/306483009

TBR=mmenke@chromium.org

Review URL: https://codereview.chromium.org/299393010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@273000 0039d316-1c4b-4281-b951-d872f2087c98

content/child/resource_dispatcher.cc

@@ -588,11 +588,8 @@ void ResourceDispatcher::CancelPendingRequest(int request_id) {
     return;
   }
 
-  SiteIsolationPolicy::OnRequestComplete(request_id);
-  PendingRequestInfo& request_info = it->second;
-  ReleaseResourcesInMessageQueue(&request_info.deferred_message_queue);
-  pending_requests_.erase(it);
-
+  // |request_id| will be removed from |pending_requests_| when
+  // OnRequestComplete returns with ERR_ABORTED.
   message_sender()->Send(new ResourceHostMsg_CancelRequest(request_id));
 }