Link GCM heartbeat with wake on wifi preference

components/gcm_driver/gcm_client_impl.cc

Index: components/gcm_driver/gcm_client_impl.cc
diff --git a/components/gcm_driver/gcm_client_impl.cc b/components/gcm_driver/gcm_client_impl.cc
index bd70ddf6a23bde1daeaeda2c5b482dc0de31280e..3bcb69fe472feaa139b05c01e65d991e2ca22eac 100644
--- a/components/gcm_driver/gcm_client_impl.cc
+++ b/components/gcm_driver/gcm_client_impl.cc
@@ -478,6 +478,10 @@ void GCMClientImpl::SetLastTokenFetchTime(const base::Time& time) {
                  weak_ptr_factory_.GetWeakPtr()));
 }
 
+MCSClient* GCMClientImpl::GetMCSClient() const {
+  return mcs_client_.get();
+}
+
 void GCMClientImpl::StartCheckin() {
   // Make sure no checkin is in progress.
   if (checkin_request_.get())