Rewrite clipboard write IPC handling to be easier to understand.

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 600 matching lines @@
       ],
       'dependencies': [
         '<(DEPTH)/base/base.gyp:base',
         '<(DEPTH)/chrome/chrome_resources.gyp:chrome_resources',
         '<(DEPTH)/chrome/chrome_resources.gyp:chrome_strings',
         '<(DEPTH)/crypto/crypto.gyp:crypto',
         '<(DEPTH)/net/net.gyp:net_resources',
         '<(DEPTH)/net/net.gyp:net',
         '<(DEPTH)/third_party/icu/icu.gyp:icui18n',
         '<(DEPTH)/third_party/icu/icu.gyp:icuuc',
+        '<(DEPTH)/ui/base/ui_base.gyp:ui_base',
       ],
       'conditions': [
         ['OS != "ios"', {
           'dependencies': [
             '<(DEPTH)/gpu/gpu.gyp:gpu_ipc',
           ],
         }, {  # OS == ios
           'sources!': [
             'common/net/net_resource_provider.cc',
             'common/net/x509_certificate_model.cc',
@@ skipping 56 matching lines @@
         'common/safe_browsing/csd.proto'
       ],
       'variables': {
         'proto_in_dir': 'common/safe_browsing',
         'proto_out_dir': 'chrome/common/safe_browsing',
       },
       'includes': [ '../build/protoc.gypi' ],
     },
   ],
 }