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

chrome/browser/extensions/extension_startup_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 <vector>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/path_service.h"
@@ skipping 32 matching lines @@
 // into the services, so we didn't start correctly.
 
 class ExtensionStartupTestBase : public InProcessBrowserTest {
  public:
   ExtensionStartupTestBase() : unauthenticated_load_allowed_(true) {
     num_expected_extensions_ = 3;
   }
 
  protected:
   // InProcessBrowserTest
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     if (load_extensions_.empty()) {
       // If no |load_extensions_| were specified, allow unauthenticated
       // extension settings to be loaded from Preferences as if they had been
       // authenticated correctly before they were handed to the ExtensionSystem.
       command_line->AppendSwitchASCII(
           switches::kForceFieldTrials,
           base::StringPrintf(
               "%s/%s/",
               chrome_prefs::internals::kSettingsEnforcementTrialName,
               chrome_prefs::internals::kSettingsEnforcementGroupNoEnforcement));
@@ skipping 231 matching lines @@
         .AppendASCII("extensions")
         .AppendASCII("app2");
     load_extensions_.push_back(fourth_extension_path.value());
   }
 };
 
 IN_PROC_BROWSER_TEST_F(ExtensionsLoadMultipleTest, Test) {
   WaitForServicesToStart(4, true);
   TestInjection(true, true);
 }