Improve GCM enum switch type safety

google_apis/gcm/engine/account_mapping.cc

Index: google_apis/gcm/engine/account_mapping.cc
diff --git a/google_apis/gcm/engine/account_mapping.cc b/google_apis/gcm/engine/account_mapping.cc
index 411d177b76177a53c84351e29d19f4e1e3ab2642..12dbafa08421918cd36a66d872f68e748fc908eb 100644
--- a/google_apis/gcm/engine/account_mapping.cc
+++ b/google_apis/gcm/engine/account_mapping.cc
@@ -37,9 +37,8 @@ std::string StatusToString(AccountMapping::MappingStatus status) {
       return kStatusMapped;
     case AccountMapping::REMOVING:
       return kStatusRemoving;
-    default:
-      NOTREACHED();
   }
+  NOTREACHED();
   return std::string();
 }