Componentize spellcheck [1]: create component and move switches there.

chrome/chrome_common.gypi

 # Copyright (c) 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': {
     # File lists shared with GN build.
     'chrome_common_sources': [
       'common/all_messages.h',
       'common/attrition_experiments.h',
@@ skipping 392 matching lines @@
           ],
         }],
         ['OS != "ios"', {
           'dependencies': [
             'common_mojo_bindings',
             '<(DEPTH)/components/components.gyp:autofill_core_common',
             '<(DEPTH)/components/components.gyp:autofill_content_common',
             '<(DEPTH)/components/components.gyp:password_manager_content_mojo_bindings',
             '<(DEPTH)/components/components.gyp:password_manager_core_common',
             '<(DEPTH)/components/components.gyp:signin_core_common',
+            '<(DEPTH)/components/components.gyp:spellcheck_common',
             '<(DEPTH)/components/components.gyp:translate_content_common',
             '<(DEPTH)/components/components.gyp:visitedlink_common',
             '<(DEPTH)/extensions/extensions.gyp:extensions_common_constants',
             '<(DEPTH)/ipc/ipc.gyp:ipc',
             '<(DEPTH)/media/media.gyp:media',
             '<(DEPTH)/third_party/re2/re2.gyp:re2',
             '<(DEPTH)/third_party/widevine/cdm/widevine_cdm.gyp:widevine_cdm_version_h',
           ],
         }, {  # OS == ios
           'sources/': [
@@ skipping 280 matching lines @@
           ],
           'dependencies': [
             'installer_util',
             '../base/base.gyp:base',
           ],
         },
       ],
     }],
   ],
 }