Add TestBrowserThreadBundle into RenderViewHostTestHarness. Kill some unnecessary real threads.

chrome/browser/download/chrome_download_manager_delegate_unittest.cc

Index: chrome/browser/download/chrome_download_manager_delegate_unittest.cc
diff --git a/chrome/browser/download/chrome_download_manager_delegate_unittest.cc b/chrome/browser/download/chrome_download_manager_delegate_unittest.cc
index d2dc590f5fc5c774fa5de28df305cee63fed589e..bd4d8e4cd779dac0e5e35ac4fce4a6958d39d2fb 100644
--- a/chrome/browser/download/chrome_download_manager_delegate_unittest.cc
+++ b/chrome/browser/download/chrome_download_manager_delegate_unittest.cc
@@ -167,18 +167,13 @@ class ChromeDownloadManagerDelegateTest :
 
   TestingPrefServiceSyncable* pref_service_;
   base::ScopedTempDir test_download_dir_;
-  content::TestBrowserThread ui_thread_;
-  content::TestBrowserThread file_thread_;
   scoped_ptr<content::MockDownloadManager> download_manager_;
   scoped_refptr<TestChromeDownloadManagerDelegate> delegate_;
   MockWebContentsDelegate web_contents_delegate_;
 };
 
 ChromeDownloadManagerDelegateTest::ChromeDownloadManagerDelegateTest()
-    : ChromeRenderViewHostTestHarness(),
-      ui_thread_(content::BrowserThread::UI, &message_loop_),
-      file_thread_(content::BrowserThread::FILE, &message_loop_),
-      download_manager_(new ::testing::NiceMock<content::MockDownloadManager>) {
+    : download_manager_(new ::testing::NiceMock<content::MockDownloadManager>) {
 }
 
 void ChromeDownloadManagerDelegateTest::SetUp() {
@@ -195,7 +190,7 @@ void ChromeDownloadManagerDelegateTest::SetUp() {
 }
 
 void ChromeDownloadManagerDelegateTest::TearDown() {
-  message_loop_.RunUntilIdle();
+  base::RunLoop().RunUntilIdle();
   delegate_->Shutdown();
   ChromeRenderViewHostTestHarness::TearDown();
 }