Move content/child/background_sync to Blink.

content/child/BUILD.gn

 # 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.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 
 if (is_component_build) {
   link_target_type = "source_set"
 } else {
@@ skipping 21 matching lines @@
   sources = [
     "appcache/appcache_backend_proxy.cc",
     "appcache/appcache_backend_proxy.h",
     "appcache/appcache_dispatcher.cc",
     "appcache/appcache_dispatcher.h",
     "appcache/appcache_frontend_impl.cc",
     "appcache/appcache_frontend_impl.h",
     "appcache/web_application_cache_host_impl.cc",
     "appcache/web_application_cache_host_impl.h",
     "assert_matching_enums.cc",
-    "background_sync/background_sync_provider.cc",
-    "background_sync/background_sync_provider.h",
     "background_sync/background_sync_type_converters.cc",
     "background_sync/background_sync_type_converters.h",
     "blink_platform_impl.cc",
     "blink_platform_impl.h",
     "blob_storage/blob_consolidation.cc",
     "blob_storage/blob_consolidation.h",
     "blob_storage/blob_message_filter.cc",
     "blob_storage/blob_message_filter.h",
     "blob_storage/blob_transport_controller.cc",
     "blob_storage/blob_transport_controller.h",
@@ skipping 238 matching lines @@
 
 # See comment at the top of //content/BUILD.gn for how this works.
 group("for_content_tests") {
   visibility = [ "//content/test/*" ]
   if (!is_component_build) {
     public_deps = [
       ":child",
     ]
   }
 }