Revert of Removing the mock-keychain related bool from GCMStore constructor

google_apis/gcm/engine/gcm_store_impl.h

Index: google_apis/gcm/engine/gcm_store_impl.h
diff --git a/google_apis/gcm/engine/gcm_store_impl.h b/google_apis/gcm/engine/gcm_store_impl.h
index a1eeff6bd12b0118a392627c227f0b1f3ed57194..a08a72c624235e24789c1e9f827a437caac219f0 100644
--- a/google_apis/gcm/engine/gcm_store_impl.h
+++ b/google_apis/gcm/engine/gcm_store_impl.h
@@ -23,7 +23,8 @@
 // all callbacks to the thread on which the GCMStoreImpl is created.
 class GCM_EXPORT GCMStoreImpl : public GCMStore {
  public:
-  GCMStoreImpl(const base::FilePath& path,
+  GCMStoreImpl(bool use_mock_keychain,
+               const base::FilePath& path,
                scoped_refptr<base::SequencedTaskRunner> blocking_task_runner);
   virtual ~GCMStoreImpl();