Remove all the browser side extensions code from Android.

extensions/extensions.gyp

 # Copyright 2013 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': [
     {
@@ skipping 479 matching lines @@
         'browser/view_type_utils.h',
       ],
       'conditions': [
         ['enable_extensions==0', {
           # Exclude all API implementations and the ExtensionsApiClient
           # interface. Moving an API from src/chrome to src/extensions implies
           # it can be cleanly disabled with enable_extensions==0.
           # TODO: Eventually the entire extensions module should not be built
           # when enable_extensions==0.
           'sources/': [
-            ['exclude', '^browser/api/'],
-          ],
-          'sources!': [
-            'browser/browser_context_keyed_service_factories.cc',
-            'browser/browser_context_keyed_service_factories.h',
+            ['exclude', '^browser/'],
           ],
           'dependencies!': [
             '../components/components.gyp:usb_service',
             '../device/serial/serial.gyp:device_serial',
           ],
         }],
         ['use_openssl==1', {
           'sources': [
             'browser/api/cast_channel/cast_auth_util_openssl.cc',
           ],
@@ skipping 373 matching lines @@
       'type': 'static_library',
       'sources': [ 'browser/api/cast_channel/cast_channel.proto' ],
       'variables': {
           'proto_in_dir': 'browser/api/cast_channel',
           'proto_out_dir': 'extensions/browser/api/cast_channel',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ]
 }