[aw] Unregister delegates from AwContents.destroy()

android_webview/native/aw_contents.cc

 // Copyright 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 "android_webview/native/aw_contents.h"
 
 #include <limits>
 
 #include "android_webview/browser/aw_browser_context.h"
 #include "android_webview/browser/aw_browser_main_parts.h"
@@ skipping 282 matching lines @@
 void AwContents::Destroy(JNIEnv* env, jobject obj) {
   java_ref_.reset();
 
   // We clear the contents_client_bridge_ here so that we break the link with
   // the java peer. This is important for the popup window case, where we are
   // swapping AwContents out that share the same java AwContentsClientBridge.
   // See b/15074651.
   AwContentsClientBridgeBase::Disassociate(web_contents_.get());
   contents_client_bridge_.reset();
 
+  // Do not wait until the WebContents are deleted asynchronously to clear
+  // the delegate and stop sending callbacks.
+  web_contents_->SetDelegate(NULL);
+
   // We do not delete AwContents immediately. Some applications try to delete
   // Webview in ShouldOverrideUrlLoading callback, which is a sync IPC from
   // Webkit.
   BrowserThread::DeleteSoon(BrowserThread::UI, FROM_HERE, this);
 }
 
 static jlong Init(JNIEnv* env, jclass, jobject browser_context) {
   // TODO(joth): Use |browser_context| to get the native BrowserContext, rather
   // than hard-code the default instance lookup here.
   scoped_ptr<WebContents> web_contents(content::WebContents::Create(
@@ skipping 854 matching lines @@
   }
 
   browser_view_renderer_.TrimMemory(level, visible);
 }
 
 void SetShouldDownloadFavicons(JNIEnv* env, jclass jclazz) {
   g_should_download_favicons = true;
 }
 
 }  // namespace android_webview