First cut at "content handling" support in Mojo.

mojo/mojo_public.gypi

 # 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': [
     {
       # GN version: //mojo/public/c/system
       'target_name': 'mojo_system',
       'type': 'static_library',
@@ skipping 151 matching lines @@
       'include_dirs': [
         '..',
       ],
     },
     {
       # GN version: //mojo/public/interfaces/service_provider:service_provider
       'target_name': 'mojo_service_provider_bindings',
       'type': 'static_library',
       'sources': [
         'public/interfaces/service_provider/service_provider.mojom',
+        'public/interfaces/service_provider/content_handler.mojom',
       ],
       'includes': [ 'public/tools/bindings/mojom_bindings_generator.gypi' ],
       'dependencies': [
         'mojo_cpp_bindings',
       ],
       'export_dependent_settings': [
         'mojo_cpp_bindings',
       ],
     },
     {
@@ skipping 40 matching lines @@
           },
           'dependencies': [
             'mojo_public_java',
           ],
           'includes': [ '../build/java.gypi' ],
         },
       ],
     }],
   ],
 }