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

chrome/common/nacl_cmd_line.cc

 // Copyright (c) 2010 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/command_line.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/logging_chrome.h"
 
 namespace nacl {
   void CopyNaClCommandLineArguments(CommandLine* cmd_line) {
     const CommandLine& browser_command_line = *CommandLine::ForCurrentProcess();
     if (logging::DialogsAreSuppressed())
       cmd_line->AppendSwitch(switches::kNoErrorDialogs);
 
     // Propagate the following switches to the NaCl loader command line (along
     // with any associated values) if present in the browser command line.
     // TODO(gregoryd): check which flags of those below can be supported.
-    static const char* const switch_names[] = {
+    static const char* const kSwitchNames[] = {
       switches::kNoSandbox,
       switches::kTestNaClSandbox,
       switches::kDisableBreakpad,
       switches::kFullMemoryCrashReport,
       switches::kEnableLogging,
       switches::kDisableLogging,
       switches::kLoggingLevel,
       switches::kEnableDCHECK,
       switches::kSilentDumpOnDCHECK,
       switches::kMemoryProfiling,
     };
-
-    for (size_t i = 0; i < arraysize(switch_names); ++i) {
-      if (browser_command_line.HasSwitch(switch_names[i])) {
-        cmd_line->AppendSwitchWithValue(
-          switch_names[i],
-          browser_command_line.GetSwitchValueASCII(switch_names[i]));
-      }
-    }
+    cmd_line->CopySwitchesFrom(browser_command_line, kSwitchNames,
+                               arraysize(kSwitchNames));
   }
 }