[debugger] fix stepping over await calls for ignition generators.

src/debug/debug.cc

Index: src/debug/debug.cc
diff --git a/src/debug/debug.cc b/src/debug/debug.cc
index 7307d6dcbcdeb9ff9d28e30df83008a5869baa7f..ca623f23714ec2347647c8b084d8be0c2c75910e 100644
--- a/src/debug/debug.cc
+++ b/src/debug/debug.cc
@@ -1400,8 +1400,8 @@ bool Debug::PrepareFunctionForBreakPoints(Handle<SharedFunctionInfo> shared) {
 
 void Debug::RecordAsyncFunction(Handle<JSGeneratorObject> generator_object) {
   if (last_step_action() <= StepOut) return;
+  if (!generator_object->function()->shared()->is_async()) return;
   DCHECK(!has_suspended_generator());
-  DCHECK(generator_object->function()->shared()->is_async());
   thread_local_.suspended_generator_ = *generator_object;
   ClearStepping();
 }