Adds new libcast_media shared library for cast_shell media

chromecast/media/media.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,
     'chromecast_branding%': 'Chromium',
+    'libcast_media_gyp%': '',
+    'use_default_libcast_media%': 1,
   },
   'targets': [
     {
       'target_name': 'media_base',
       'type': '<(component)',
       'dependencies': [
         '../../base/base.gyp:base',
         '../../crypto/crypto.gyp:crypto',
         '../../third_party/widevine/cdm/widevine_cdm.gyp:widevine_cdm_version_h',
+        '<(libcast_media_gyp):libcast_media_1.0',
       ],
       'sources': [
         'base/decrypt_context.cc',
         'base/decrypt_context.h',
         'base/decrypt_context_clearkey.cc',
         'base/decrypt_context_clearkey.h',
         'base/key_systems_common.cc',
         'base/key_systems_common.h',
         'base/media_caps.cc',
         'base/media_caps.h',
@@ skipping 259 matching lines @@
         'cma/test/frame_segmenter_for_test.h',
         'cma/test/media_component_device_feeder_for_test.cc',
         'cma/test/media_component_device_feeder_for_test.h',
         'cma/test/mock_frame_consumer.cc',
         'cma/test/mock_frame_consumer.h',
         'cma/test/mock_frame_provider.cc',
         'cma/test/mock_frame_provider.h',
         'cma/test/run_all_unittests.cc',
       ],
     },
+  ], # end of targets
+  'conditions': [
+    ['use_default_libcast_media==1', {
+      'targets': [
+        {
+          'target_name': 'libcast_media_1.0',
+          'type': 'shared_library',
+          'dependencies': [
+            '../../chromecast/chromecast.gyp:cast_public_api'
+          ],
+          'include_dirs': [
+            '../..',
+          ],
+          'sources': [
+            'base/cast_media_default.cc',
+          ],
+        }
+      ]
+    }],
   ],
 }