Tidy up releasing of AssociatedURLLoader's client references.

third_party/WebKit/Source/web/AssociatedURLLoader.cpp

 /*
  * Copyright (C) 2010, 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 124 matching lines @@
     void willFollowRedirect(ResourceRequest& /*newRequest*/, const ResourceResponse& /*redirectResponse*/) override;
 
     // Sets an error to be reported back to the client, asychronously.
     void setDelayedError(const ResourceError&);
 
     // Enables forwarding of error notifications to the WebURLLoaderClient. These must be
     // deferred until after the call to AssociatedURLLoader::loadAsynchronously() completes.
     void enableErrorNotifications();
 
     // Stops loading and releases the DocumentThreadableLoader as early as possible.
-    void clearClient() { m_client = 0; }
+    WebURLLoaderClient* releaseClient()
+    {
+        WebURLLoaderClient* client = m_client;
+        m_client = nullptr;
+        return client;
+    }
 
 private:
     ClientAdapter(AssociatedURLLoader*, WebURLLoaderClient*, const WebURLLoaderOptions&);
 
     void notifyError(Timer<ClientAdapter>*);
 
     AssociatedURLLoader* m_loader;
     WebURLLoaderClient* m_client;
     WebURLLoaderOptions m_options;
     WebURLError m_error;
@@ skipping 87 matching lines @@
     m_client->didReceiveCachedMetadata(m_loader, data, dataLength);
 }
 
 void AssociatedURLLoader::ClientAdapter::didFinishLoading(unsigned long identifier, double finishTime)
 {
     if (!m_client)
         return;
 
     m_loader->clientAdapterDone();
 
-    auto client = m_client;
-    m_client = nullptr;
-    client->didFinishLoading(m_loader, finishTime, WebURLLoaderClient::kUnknownEncodedDataLength);
+    releaseClient()->didFinishLoading(m_loader, finishTime, WebURLLoaderClient::kUnknownEncodedDataLength);
     // |this| may be dead here.
 }
 
 void AssociatedURLLoader::ClientAdapter::didFail(const ResourceError& error)
 {
     if (!m_client)
         return;
 
     m_loader->clientAdapterDone();
 
@@ skipping 17 matching lines @@
         m_errorTimer.startOneShot(0, BLINK_FROM_HERE);
 }
 
 void AssociatedURLLoader::ClientAdapter::notifyError(Timer<ClientAdapter>* timer)
 {
     ASSERT_UNUSED(timer, timer == &m_errorTimer);
 
     if (!m_client)
         return;
 
-    auto client = m_client;
-    m_client = nullptr;
-    client->didFail(m_loader, m_error);
+    releaseClient()->didFail(m_loader, m_error);
     // |this| may be dead here.
 }
 
 class AssociatedURLLoader::Observer final : public GarbageCollected<Observer>, public ContextLifecycleObserver {
     USING_GARBAGE_COLLECTED_MIXIN(Observer);
 public:
     Observer(AssociatedURLLoader* parent, Document* document)
         : ContextLifecycleObserver(document)
         , m_parent(parent)
     {
@@ skipping 99 matching lines @@
         // FIXME: return meaningful error codes.
         m_clientAdapter->didFail(ResourceError());
     }
     m_clientAdapter->enableErrorNotifications();
 }
 
 void AssociatedURLLoader::cancel()
 {
     disposeObserver();
     cancelLoader();
-    m_client = nullptr;
+    releaseClient();
 }
 
 void AssociatedURLLoader::clientAdapterDone()
 {
     disposeObserver();
-    m_client = nullptr;
+    releaseClient();
 }
 
 void AssociatedURLLoader::cancelLoader()
 {
     if (!m_clientAdapter)
         return;
 
     // Prevent invocation of the WebURLLoaderClient methods.
-    m_clientAdapter->clearClient();
+    m_clientAdapter->releaseClient();
 
     if (m_loader) {
         m_loader->cancel();
         m_loader.clear();
     }
     m_clientAdapter.clear();
 }
 
 void AssociatedURLLoader::setDefersLoading(bool defersLoading)
 {
     if (m_loader)
         m_loader->setDefersLoading(defersLoading);
 }
 
 void AssociatedURLLoader::setLoadingTaskRunner(blink::WebTaskRunner*)
 {
     // TODO(alexclarke): Maybe support this one day if it proves worthwhile.
 }
 
 void AssociatedURLLoader::documentDestroyed()
 {
     disposeObserver();
     cancelLoader();
 
     if (!m_client)
         return;
 
-    WebURLLoaderClient* client = m_client;
-    m_client = nullptr;
-    client->didFail(this, ResourceError());
+    releaseClient()->didFail(this, ResourceError());
     // |this| may be dead here.
 }
 
 void AssociatedURLLoader::disposeObserver()
 {
     if (!m_observer)
         return;
 
     // TODO(tyoshino): Remove this assert once Document is fixed so that
     // contextDestroyed() is invoked for all kinds of Documents.
@@ skipping 10 matching lines @@
     // there could be a WebURLLoader instance behind the
     // DocumentThreadableLoader instance. So, for safety, we chose to just
     // crash here.
     RELEASE_ASSERT(ThreadState::current());
 
     m_observer->dispose();
     m_observer = nullptr;
 }
 
 } // namespace blink