Adds initial key systems support for Chromecast.

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.
 
 {
   'targets': [
     {
+      'target_name': 'media_base',
+      'type': '<(component)',
+      'dependencies': [
+        '../../base/base.gyp:base',
+        '../../third_party/widevine/cdm/widevine_cdm.gyp:widevine_cdm_version_h',
+      ],
+      'sources': [
+        'base/key_systems_common.cc',
+        'base/key_systems_common.h',
+      ],
+    },
+    {
       'target_name': 'cma_base',
       'type': '<(component)',
       'dependencies': [
         '../../base/base.gyp:base',
         '../../media/media.gyp:media',
       ],
       'include_dirs': [
         '../..',
       ],
       'sources': [
@@ skipping 101 matching lines @@
         'cma/base/mock_frame_provider.h',
         'cma/base/run_all_unittests.cc',
         'cma/filters/demuxer_stream_adapter_unittest.cc',
         'cma/ipc/media_message_fifo_unittest.cc',
         'cma/ipc/media_message_unittest.cc',
         'cma/ipc_streamer/av_streamer_unittest.cc',
       ],
     },
   ],
 }