Update references to the extension messaging APIs to point to the "runtime"

chrome/browser/resources/file_manager/js/file_copy_manager.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.
 
 if (chrome.extension) {
   function getContentWindows() {
     return chrome.extension.getViews();
   }
 }
 
@@ skipping 898 matching lines @@
               onStartTransfer();
               sourceEntry.copyTo(dirEntry, fileName, onSuccessTransfer,
                                                      onFailTransfer);
             },
             onFilesystemError);
         return;
       }
 
       function onFileTransferCompleted() {
         self.cancelCallback_ = null;
-        if (chrome.extension.lastError) {
+        if (chrome.runtime.lastError) {
           onFailTransfer({
-            code: chrome.extension.lastError.message,
+            code: chrome.runtime.lastError.message,
             toGDrive: task.targetOnGData,
             sourceFileUrl: sourceFileUrl
           });
         } else {
           targetDirEntry.getFile(targetRelativePath, {}, onSuccessTransfer,
                                                          onFailTransfer);
         }
       }
 
       self.cancelCallback_ = function() {
@@ skipping 322 matching lines @@
  */
 FileCopyManager.prototype.sendDeleteEvent_ = function(task, reason) {
   this.sendEvent_('delete', {
     reason: reason,
     id: task.id,
     urls: task.entries.map(function(e) {
       return util.makeFilesystemUrl(e.fullPath);
     })
   });
 };