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

chrome/browser/extensions/api/media_galleries/media_galleries_watch_apitest.cc

 // Copyright 2014 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.
 //
 // MediaGalleries gallery watch API browser tests.
 
 #include "base/files/file_path.h"
 #include "base/files/file_path_watcher.h"
 #include "base/files/file_util.h"
 #include "base/run_loop.h"
@@ skipping 63 matching lines @@
 ///////////////////////////////////////////////////////////////////////////////
 
 class MediaGalleriesGalleryWatchApiTest : public ExtensionApiTest {
  public:
   MediaGalleriesGalleryWatchApiTest()
       : extension_(NULL), background_host_(NULL) {}
   ~MediaGalleriesGalleryWatchApiTest() override {}
 
  protected:
   // ExtensionApiTest overrides.
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     ExtensionApiTest::SetUpCommandLine(command_line);
     command_line->AppendSwitchASCII(
         extensions::switches::kWhitelistedExtensionID, kTestExtensionId);
   }
   void SetUpOnMainThread() override {
     ExtensionApiTest::SetUpOnMainThread();
     ensure_media_directories_exists_.reset(new EnsureMediaDirectoriesExists);
     extension_ = LoadExtension(test_data_dir_.AppendASCII(kTestExtensionPath));
     GetBackgroundHostForTestExtension();
     CreateTestGallery();
@@ skipping 256 matching lines @@
   // Remove all gallery watchers.
   ExecuteCmdAndCheckReply(kRemoveAllGalleryWatchCmd, kRemoveAllGalleryWatchOK);
 
   // Gallery watchers removed. chrome.mediaGalleries.getAllGalleryWatch
   // should return an empty list.
   ExtensionTestMessageListener final_get_all_check_finished(
       kNoGalleryWatchesInstalled, false /* no reply */);
   ExecuteCmdAndCheckReply(kGetAllWatchedGalleryIdsCmd, kGetAllGalleryWatchOK);
   EXPECT_TRUE(final_get_all_check_finished.WaitUntilSatisfied());
 }