Move content/child/background_sync to Blink.

content/child/service_worker/web_service_worker_registration_impl.cc

Index: content/child/service_worker/web_service_worker_registration_impl.cc
diff --git a/content/child/service_worker/web_service_worker_registration_impl.cc b/content/child/service_worker/web_service_worker_registration_impl.cc
index 65a04631523ecfe9825227ac252593d8a27d8f72..34be8bd86e14fec040709b7feb270b22c63d673a 100644
--- a/content/child/service_worker/web_service_worker_registration_impl.cc
+++ b/content/child/service_worker/web_service_worker_registration_impl.cc
@@ -191,6 +191,10 @@ int64_t WebServiceWorkerRegistrationImpl::registration_id() const {
   return handle_ref_->registration_id();
 }
 
+int64_t WebServiceWorkerRegistrationImpl::registrationId() const {
+  return registration_id();
+}

[falken, 2016/11/11 07:59:17]

For code health, can we remove registration_id() and just use registrationId()?

[falken, 2016/11/11 08:08:07]

(it's OK to do this as a followup patch, perhaps just add a TODO in the header
file)

[adithyas, 2016/11/11 15:11:56]

The function is used in 6 other files, so I'll make the changes in another
patch. Adding a TODO for now.

+
 // static
 std::unique_ptr<blink::WebServiceWorkerRegistration::Handle>
 WebServiceWorkerRegistrationImpl::CreateHandle(