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

chrome/browser/pref_service_uitest.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 <string>
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "base/test/test_file_util.h"
@@ skipping 31 matching lines @@
     // Copy only the Local State file, the rest will be automatically created
     ASSERT_TRUE(file_util::CopyFile(reference_pref_file, tmp_pref_file_));
 
 #if defined(OS_WIN)
     // Make the copy writable.  On POSIX we assume the umask allows files
     // we create to be writable.
     ASSERT_TRUE(::SetFileAttributesW(tmp_pref_file_.value().c_str(),
         FILE_ATTRIBUTE_NORMAL));
 #endif
 
-    launch_arguments_.AppendSwitchWithValue(switches::kUserDataDir,
-                                            tmp_profile_.ToWStringHack());
+    launch_arguments_.AppendSwitchPath(switches::kUserDataDir, tmp_profile_);
   }
 
   bool LaunchAppWithProfile() {
     if (!file_util::PathExists(tmp_pref_file_))
       return false;
     UITest::SetUp();
     return true;
   }
 
   void TearDown() {
@@ skipping 62 matching lines @@
 
   // Find if launched window is maximized.
   bool is_window_maximized = false;
   ASSERT_TRUE(window->IsMaximized(&is_window_maximized));
   bool is_maximized = false;
   EXPECT_TRUE(root_dict->GetBoolean(kBrowserWindowPlacement + L".maximized",
       &is_maximized));
   EXPECT_EQ(is_maximized, is_window_maximized);
 }
 #endif