Fix chrome.runtime.sendMessage background page memory leak.

chrome/renderer/resources/extensions/messaging.js

 // Copyright (c) 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.
 
 // This contains unprivileged javascript APIs for extensions and apps.  It
 // can be loaded by any extension-related context, such as content scripts or
 // background pages. See user_script_slave.cc for script that is loaded by
 // content scripts only.
 
   // TODO(kalman): factor requiring chrome out of here.
@@ skipping 143 matching lines @@
       if (chrome.extension) {
         requestEvent = isExternal ? chrome.extension.onRequestExternal
                                   : chrome.extension.onRequest;
       }
     }
     if (!requestEvent)
       return false;
     if (!requestEvent.hasListeners())
       return false;
     var port = createPort(portId, channelName);
-    port.onMessage.addListener(function(request) {
+
+    function messageListener(request) {
       var responseCallbackPreserved = false;
       var responseCallback = function(response) {
         if (port) {
           port.postMessage(response);
           port.destroy_();
           port = null;
         } else {
           // We nulled out port when sending the response, and now the page
           // is trying to send another response for the same request.
           handleSendRequestError(isSendMessage, responseCallbackPreserved,
@@ skipping 16 matching lines @@
         var rv = requestEvent.dispatch(request, sender, responseCallback);
         responseCallbackPreserved =
             rv && rv.results && $Array.indexOf(rv.results, true) > -1;
         if (!responseCallbackPreserved && port) {
           // If they didn't access the response callback, they're not
           // going to send a response, so clean up the port immediately.
           port.destroy_();
           port = null;
         }
       }
-    });
+    }
+
+    port.onDestroy_ = function() {
+      port.onMessage.removeListener(messageListener);
+    };
+    port.onMessage.addListener(messageListener);
+
     var eventName = (isSendMessage ?
           (isExternal ?
               "runtime.onMessageExternal" : "runtime.onMessage") :
           (isExternal ?
               "extension.onRequestExternal" : "extension.onRequest"));
     logActivity.LogEvent(targetExtensionId,
                          eventName,
                          [sourceExtensionId, sourceUrl]);
     return true;
   }
@@ skipping 151 matching lines @@
 exports.Port = Port;
 exports.createPort = createPort;
 exports.sendMessageImpl = sendMessageImpl;
 exports.sendMessageUpdateArguments = sendMessageUpdateArguments;
 
 // For C++ code to call.
 exports.hasPort = hasPort;
 exports.dispatchOnConnect = dispatchOnConnect;
 exports.dispatchOnDisconnect = dispatchOnDisconnect;
 exports.dispatchOnMessage = dispatchOnMessage;