GN: Add mojo_shell_tests, get more things working on android

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 233 matching lines @@
         'public/cpp/application/lib/weak_service_provider.h',
       ],
       'dependencies': [
         'mojo_application_bindings',
       ],
       'export_dependent_settings': [
         'mojo_application_bindings',
       ],
     },
     {
+      # GN version: //mojo/public/cpp/application:standalone"
       'target_name': 'mojo_application_standalone',
       'type': 'static_library',
       'sources': [
         'public/cpp/application/lib/application_impl_standalone.cc',
       ],
       'dependencies': [
         'mojo_application_base',
       ],
       'export_dependent_settings': [
         'mojo_application_base',
@@ skipping 21 matching lines @@
           },
           'dependencies': [
             'mojo_public_java',
           ],
           'includes': [ '../build/java.gypi' ],
         },
       ],
     }],
   ],
 }