Make callers of CommandLine use it via the base:: namespace.

chrome/browser/extensions/api/downloads/downloads_api_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.
 
 // Disable everything on windows only. http://crbug.com/306144
 #ifndef OS_WIN
 
 #include <algorithm>
 
 #include "base/files/file_util.h"
@@ skipping 3840 matching lines @@
 #else
 #define MAYBE_DownloadExtensionTest_OnDeterminingFilename_InterruptedResume \
     DownloadExtensionTest_OnDeterminingFilename_InterruptedResume
 #endif
 
 // Test download interruption while extensions determining filename. Should not
 // re-dispatch onDeterminingFilename.
 IN_PROC_BROWSER_TEST_F(
     DownloadExtensionTest,
     MAYBE_DownloadExtensionTest_OnDeterminingFilename_InterruptedResume) {
-  CommandLine::ForCurrentProcess()->AppendSwitch(
+  base::CommandLine::ForCurrentProcess()->AppendSwitch(
       switches::kEnableDownloadResumption);
   LoadExtension("downloads_split");
   ASSERT_TRUE(StartEmbeddedTestServer());
   ASSERT_TRUE(test_server()->Start());
   GoOnTheRecord();
   content::RenderProcessHost* host = AddFilenameDeterminer();
 
   // Start a download.
   DownloadItem* item = NULL;
   {
@@ skipping 280 matching lines @@
   EXPECT_EQ(downloads::FILENAME_CONFLICT_ACTION_PROMPT, conflict_action);
   EXPECT_FALSE(warnings.empty());
   EXPECT_EQ(Warning::kDownloadFilenameConflict,
             warnings.begin()->warning_type());
   EXPECT_EQ("incumbent", warnings.begin()->extension_id());
 }
 
 }  // namespace extensions
 
 #endif  // http://crbug.com/3061144