CommandLine: add a CopySwitchesFrom() for copying from another CommandLine

chrome/renderer/renderer_main_unittest.cc

 // Copyright (c) 2009 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 "base/message_loop.h"
 #include "base/multiprocess_test.h"
 #include "base/process_util.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/main_function_params.h"
 #include "ipc/ipc_channel.h"
@@ skipping 61 matching lines @@
   void OnMessageReceived(const IPC::Message& message) {
     // We shouldn't receive any messages
     ASSERT_TRUE(false);
   }
 };
 
 MULTIPROCESS_TEST_MAIN(SimpleRenderer) {
   SandboxInitWrapper dummy_sandbox_init;
   CommandLine cl(*CommandLine::ForCurrentProcess());
   cl.AppendSwitchWithValue(switches::kProcessChannelID,
-                           ASCIIToWide(kRendererTestChannelName));
+                           kRendererTestChannelName);
 
   MainFunctionParams dummy_params(cl, dummy_sandbox_init, NULL);
   return RendererMain(dummy_params);
 }
 
 TEST_F(RendererMainTest, CreateDestroy) {
   SuicidalListener listener;
   IPC::Channel control_channel(kRendererTestChannelName,
                                IPC::Channel::MODE_SERVER,
                                &listener);
   base::ProcessHandle renderer_pid = SpawnChild(L"SimpleRenderer",
                                                 &control_channel);
 
   control_channel.Connect();
   MessageLoop::current()->Run();
 
   // The renderer should exit when we close the channel.
   control_channel.Close();
 
   EXPECT_TRUE(base::WaitForSingleProcess(renderer_pid, 5000));
 }
 #endif  // defined(OS_POSIX)