[GCM] Stop/restart GCM when the state is forced off/on

google_apis/gcm/engine/gcm_store.h

Index: google_apis/gcm/engine/gcm_store.h
diff --git a/google_apis/gcm/engine/gcm_store.h b/google_apis/gcm/engine/gcm_store.h
index d725118851a3a3978e8938c382e698b890b8d082..4387042a8447cbf53d794a280cb3b135149d48c9 100644
--- a/google_apis/gcm/engine/gcm_store.h
+++ b/google_apis/gcm/engine/gcm_store.h
@@ -68,6 +68,9 @@ class GCM_EXPORT GCMStore {
   // caller.
   virtual void Load(const LoadCallback& callback) = 0;
 
+  // Close the persistent store.
+  virtual void Close() = 0;
+
   // Clears the GCM store of all data.
   virtual void Destroy(const UpdateCallback& callback) = 0;