Add initial home card impl.

athena/athena.gyp

 # Copyright 2014 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,
   },
   'targets': [
     {
       'target_name': 'athena_lib',
       'type': '<(component)',
       'dependencies': [
         '../ui/aura/aura.gyp:aura',
         '../ui/views/views.gyp:views',
         '../ui/accessibility/accessibility.gyp:ax_gen',
         '../skia/skia.gyp:skia',
       ],
       'defines': [
         'ATHENA_IMPLEMENTATION',
       ],
       'sources': [
         # All .cc, .h under athena, except unittests
         'athena_export.h',
+        'home/home_card_delegate_view.cc',
+        'home/home_card_delegate_view.h',
+        'home/home_card_impl.cc',
+        'home/public/home_card.h',
+        'screen/background_controller.cc',
         'screen/background_controller.h',
-        'screen/background_controller.cc',
         'screen/public/screen_manager.h',
         'screen/screen_manager_impl.cc',
         'wm/public/window_manager.h',
         'wm/window_manager_impl.cc',
       ],
     },
   ],
 }