Add the partial screen magnifier to Chrome OS.

ash/ash.gyp

 # Copyright (c) 2012 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,
     'grit_out_dir': '<(SHARED_INTERMEDIATE_DIR)/chrome',
   },
 
@@ skipping 109 matching lines @@
         'launcher/launcher_view.cc',
         'launcher/launcher_view.h',
         'launcher/overflow_bubble.cc',
         'launcher/overflow_bubble.h',
         'launcher/overflow_button.cc',
         'launcher/overflow_button.h',
         'launcher/tabbed_launcher_button.cc',
         'launcher/tabbed_launcher_button.h',
         'magnifier/magnification_controller.cc',
         'magnifier/magnification_controller.h',
+        'magnifier/partial_magnification_controller.cc',
+        'magnifier/partial_magnification_controller.h',
         'keyboard_overlay/keyboard_overlay_delegate.cc',
         'keyboard_overlay/keyboard_overlay_delegate.h',
         'keyboard_overlay/keyboard_overlay_view.cc',
         'keyboard_overlay/keyboard_overlay_view.h',
         'root_window_controller.cc',
         'root_window_controller.h',
         'rotator/screen_rotation.cc',
         'rotator/screen_rotation.h',
         'screen_ash.cc',
         'screen_ash.h',
@@ skipping 501 matching lines @@
             'shell/cocoa/app-Info.plist',
           ],
           'xcode_settings': {
             'INFOPLIST_FILE': 'shell/cocoa/app-Info.plist',
           },
         }],
       ],
     },
   ],
 }