Introduce shared_memory_support media target for PPAPI

ppapi/ppapi_shared_untrusted.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,
   },
   'includes': [
     '../build/common_untrusted.gypi',
@@ skipping 18 matching lines @@
           'include_dirs': [
             '..',
             '../third_party/khronos',
           ],
           'dependencies': [
             '../native_client/tools.gyp:prep_toolchain',
             '../base/base_untrusted.gyp:base_untrusted',
             '../gpu/command_buffer/command_buffer_untrusted.gyp:gles2_utils_untrusted',
             '../gpu/gpu_untrusted.gyp:command_buffer_client_untrusted',
             '../gpu/gpu_untrusted.gyp:gles2_implementation_untrusted',
+            '../media/media_untrusted.gyp:shared_memory_support_untrusted',
           ],
         },
       ],
     }],
   ],
 }