Add support for GCM subtypes to desktop Instance ID implementation

components/gcm_driver/instance_id/instance_id_impl.cc

Index: components/gcm_driver/instance_id/instance_id_impl.cc
diff --git a/components/gcm_driver/instance_id/instance_id_impl.cc b/components/gcm_driver/instance_id/instance_id_impl.cc
index 74c708a560ac0f07ae46f9e6bb3b6a89d5076b30..8e7e726ff4548986ac59333c295dfbbfde628c40 100644
--- a/components/gcm_driver/instance_id/instance_id_impl.cc
+++ b/components/gcm_driver/instance_id/instance_id_impl.cc
@@ -49,8 +49,9 @@ InstanceID::Result GCMClientResultToInstanceIDResult(
 }  // namespace
 
 // static
-std::unique_ptr<InstanceID> InstanceID::Create(const std::string& app_id,
-                                               gcm::GCMDriver* gcm_driver) {
+std::unique_ptr<InstanceID> InstanceID::CreateInternal(
+    const std::string& app_id,
+    gcm::GCMDriver* gcm_driver) {
   return base::WrapUnique(new InstanceIDImpl(app_id, gcm_driver));
 }