Refactor chromedriver's script execution to reduce amount of custom Value parsing.

chrome/chrome.gyp

 # Copyright (c) 2011 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.
 {
   'variables': {
     'chromium_code': 1,
 
     'variables': {
       'version_py_path': 'tools/build/version.py',
       'version_path': 'VERSION',
@@ skipping 1531 matching lines @@
              'test/automation/browser_proxy.cc',
              'test/automation/browser_proxy.h',
              'test/automation/dom_element_proxy.cc',
              'test/automation/dom_element_proxy.h',
              'test/automation/extension_proxy.cc',
              'test/automation/extension_proxy.h',
              'test/automation/javascript_execution_controller.cc',
              'test/automation/javascript_execution_controller.h',
              'test/automation/tab_proxy.cc',
              'test/automation/tab_proxy.h',
+             'test/automation/value_conversion_traits.cc',
+             'test/automation/value_conversion_traits.h',
+             'test/automation/value_conversion_util.h',
              'test/automation/window_proxy.cc',
              'test/automation/window_proxy.h',
           ],
         },
         {
           'target_name': 'crash_service',
           'type': 'executable',
           'dependencies': [
             'app/policy/cloud_policy_codegen.gyp:policy',
             'common_constants',
@@ skipping 146 matching lines @@
             'destination': '<(PRODUCT_DIR)',
             'files': [
               '<(INTERMEDIATE_DIR)/repack/chrome.pak'
             ],
           },
         ],
       }],  # targets
     }],  # os_posix == 1 and OS != "mac"
   ],  # 'conditions'
 }