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

tools/gn/command_ls.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.
 
 #include <algorithm>
 #include <set>
 
 #include "base/command_line.h"
 #include "tools/gn/commands.h"
 #include "tools/gn/label_pattern.h"
@@ skipping 52 matching lines @@
   if (args.size() != 1 && args.size() != 2) {
     Err(Location(), "You're holding it wrong.",
         "Usage: \"gn ls <build dir> [<label_pattern>]\"").PrintToStdout();
     return 1;
   }
 
   Setup* setup = new Setup;
   if (!setup->DoSetup(args[0], false) || !setup->Run())
     return 1;
 
-  const CommandLine* cmdline = CommandLine::ForCurrentProcess();
+  const base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
   bool all_toolchains = cmdline->HasSwitch("all-toolchains");
 
   // Find matching targets.
   std::vector<const Target*> matches;
   if (args.size() == 2) {
     // Given a pattern, match it.
     if (!ResolveTargetsFromCommandLinePattern(setup, args[1], all_toolchains,
                                               &matches))
       return 1;
   } else if (all_toolchains) {
@@ skipping 26 matching lines @@
       OutputString(match.GetUserVisibleName(
           match.GetToolchainLabel() != default_tc_label));
       OutputString("\n");
     }
   }
 
   return 0;
 }
 
 }  // namespace commands