A few minor changes to the chrome.downloads extension API

chrome/browser/download/download_danger_prompt_browsertest.cc

 // 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.
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "chrome/browser/download/download_danger_prompt.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
@@ skipping 71 matching lines @@
   }
 
   void CreatePrompt() {
     prompt_ = DownloadDangerPrompt::Create(
         &download_,
         browser()->tab_strip_model()->GetActiveWebContents(),
         false,
         base::Bind(&DownloadDangerPromptTest::PromptCallback, this,
                    DownloadDangerPrompt::ACCEPT),
         base::Bind(&DownloadDangerPromptTest::PromptCallback, this,
-                   DownloadDangerPrompt::CANCEL));
+                   DownloadDangerPrompt::CANCEL),
+        base::Bind(&DownloadDangerPromptTest::PromptDestroyed, this));
     content::RunAllPendingInMessageLoop();
   }
 
   void PromptCallback(DownloadDangerPrompt::Action action) {
     EXPECT_FALSE(did_receive_callback_);
     EXPECT_EQ(expected_action_, action);
     did_receive_callback_ = true;
+  }
+
+  void PromptDestroyed() {
     prompt_ = NULL;
   }
 
   content::MockDownloadItem download_;
   content::DownloadItem::Observer* download_observer_;
   DownloadDangerPrompt* prompt_;
   DownloadDangerPrompt::Action expected_action_;
   bool did_receive_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadDangerPromptTest);
@@ skipping 35 matching lines @@
   download_observer()->OnDownloadUpdated(&download());
   SimulatePromptAction(DownloadDangerPrompt::ACCEPT);
   VerifyExpectations();
 
   // If the containing tab is closed, the dialog should be canceled.
   OpenNewTab();
   SetUpExpectations(DownloadDangerPrompt::CANCEL);
   chrome::CloseTab(browser());
   VerifyExpectations();
 }