Use the new java_cpp_enum rule in content.

android_webview/libwebviewchromium.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.
 {
   'type': 'shared_library',
   'android_unmangled_name': 1,
   'dependencies': [
     'android_webview_common',
   ],
   'conditions': [
     [ 'android_webview_build==1', {
       # When building inside the android tree we also need to depend on all
       # the java sources generated from templates which will be needed by
       # android_webview_java in android_webview/java_library_common.mk.
       'dependencies': [
         '../base/base.gyp:base_java_application_state',
         '../base/base.gyp:base_java_memory_pressure_level_list',
         '../content/content.gyp:content_gamepad_mapping',
         '../content/content.gyp:gesture_event_type_java',
         '../content/content.gyp:popup_item_type_java',
         '../content/content.gyp:result_codes_java',
         '../content/content.gyp:screen_orientation_values_java',
         '../content/content.gyp:selection_event_type_java',
         '../content/content.gyp:speech_recognition_error_java',
+        '../content/content.gyp:top_controls_state_java',
         '../media/media.gyp:media_android_imageformat_list',
         '../net/net.gyp:cert_verify_status_android_java',
         '../net/net.gyp:certificate_mime_types_java',
         '../net/net.gyp:net_errors_java',
         '../net/net.gyp:private_key_types_java',
         '../ui/android/ui_android.gyp:bitmap_format_java',
         '../ui/android/ui_android.gyp:page_transition_types_java',
         '../ui/android/ui_android.gyp:window_open_disposition_java',
       ],
       # Enable feedback-directed optimisation for the library when building in
@@ skipping 22 matching lines @@
       'libraries': [
         '-lgabi++',
       ],
     }],
   ],
   'sources': [
     'lib/main/webview_entry_point.cc',
   ],
 }