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

chrome/browser/first_run/first_run_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 <string>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/prefs/pref_service.h"
@@ skipping 83 matching lines @@
 
     // This invokes BrowserMain, and does the import, so must be done last.
     InProcessBrowserTest::SetUp();
   }
 
   void TearDown() override {
     EXPECT_TRUE(base::DeleteFile(prefs_file_, false));
     InProcessBrowserTest::TearDown();
   }
 
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     InProcessBrowserTest::SetUpCommandLine(command_line);
     command_line->AppendSwitch(switches::kForceFirstRun);
     EXPECT_EQ(first_run::AUTO_IMPORT_NONE, first_run::auto_import_state());
 
     extensions::ComponentLoader::EnableBackgroundExtensionsForTesting();
   }
 
   void SetMasterPreferencesForTest(const char text[]) {
     text_.reset(new std::string(text));
   }
@@ skipping 125 matching lines @@
     "  \"homepage\": \"example.com\",\n"
     "  \"homepage_is_newtabpage\": false\n"
     "}\n";
 // A test fixture that will run in a first run scenario with master_preferences
 // set to kWithTrackedPrefs. Parameterizable on the SettingsEnforcement
 // experiment to be forced.
 class FirstRunMasterPrefsWithTrackedPreferences
     : public FirstRunMasterPrefsBrowserTestT<kWithTrackedPrefs>,
       public testing::WithParamInterface<std::string> {
  public:
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     FirstRunMasterPrefsBrowserTestT::SetUpCommandLine(command_line);
     command_line->AppendSwitchASCII(
         switches::kForceFieldTrials,
         std::string(chrome_prefs::internals::kSettingsEnforcementTrialName) +
             "/" + GetParam() + "/");
   }
 };
 
 // http://crbug.com/314221
 #if defined(GOOGLE_CHROME_BUILD) && (defined(OS_MACOSX) || defined(OS_LINUX))
@@ skipping 26 matching lines @@
     FirstRunMasterPrefsWithTrackedPreferences,
     testing::Values(
         chrome_prefs::internals::kSettingsEnforcementGroupNoEnforcement,
         chrome_prefs::internals::kSettingsEnforcementGroupEnforceAlways,
         chrome_prefs::internals::
             kSettingsEnforcementGroupEnforceAlwaysWithDSE,
         chrome_prefs::internals::
             kSettingsEnforcementGroupEnforceAlwaysWithExtensionsAndDSE));
 
 #endif  // !defined(OS_CHROMEOS)