Fix throws flag

Author: kavon

lib/Frontend/CompilerInvocation.cpp

@@ -2599,7 +2599,7 @@ static bool ParseSILArgs(SILOptions &Opts, ArgList &Args,
   Opts.EnableAsyncDemotion |= Args.hasArg(OPT_enable_async_demotion);
   Opts.EnableThrowsPrediction = Args.hasFlag(
       OPT_enable_throws_prediction, OPT_disable_throws_prediction,
-      /*default=*/false);
+      Opts.EnableThrowsPrediction);
   Opts.EnableActorDataRaceChecks |= Args.hasFlag(
       OPT_enable_actor_data_race_checks,
       OPT_disable_actor_data_race_checks, /*default=*/false);