Add InvalidArgument error type for NotificationDatabase.

content/browser/notifications/notification_database.cc

Index: content/browser/notifications/notification_database.cc
diff --git a/content/browser/notifications/notification_database.cc b/content/browser/notifications/notification_database.cc
index 3b4ba9fc5e3bdcced1bc1f27903b082fba453636..31aa8f2a77e87bfe8cc53b6e4a86e23d9c57f2b4 100644
--- a/content/browser/notifications/notification_database.cc
+++ b/content/browser/notifications/notification_database.cc
@@ -58,8 +58,9 @@ NotificationDatabase::Status LevelDBStatusToStatus(
     return NotificationDatabase::STATUS_IO_ERROR;
   else if (status.IsNotSupportedError())
     return NotificationDatabase::STATUS_NOT_SUPPORTED;
+  else if (status.IsInvalidArgument())
+    return NotificationDatabase::STATUS_INVALID_ARGUMENT;
 
-  // TODO(cmumford): Once leveldb 1.19 is released add IsInvalidArgument().
   return NotificationDatabase::STATUS_ERROR_FAILED;
 }