[runtime] set AsyncFunctionNext/Throw to adapt arguments

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index a8fe6bb7b61b2524c6f84313370ab665b234424e..edd3ac728288e6b5b8a289146637f784f5e90cf4 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -834,7 +834,11 @@ int JavaScriptFrame::GetNumberOfIncomingArguments() const {
   DCHECK(can_access_heap_objects() &&
          isolate()->heap()->gc_state() == Heap::NOT_IN_GC);
 
-  return function()->shared()->internal_formal_parameter_count();
+  int param_count = function()->shared()->internal_formal_parameter_count();
+  if (param_count == SharedFunctionInfo::kDontAdaptArgumentsSentinel) {
+    param_count = function()->shared()->length();
+  }
+  return param_count;

[Dan Ehrenberg, 2016/05/18 18:58:02]

Why is this change needed?

[caitp (gmail), 2016/05/18 19:03:43]

for anything with DontAdaptArguments() called on the shared function info, it
has this sentinel value (which is -1) --- so this breaks stuff.

AsyncFunctionNext/Throw don't (and shouldn't) need to adapt arguments, though.

An alternative fix would be to just make these functions adapt arguments (which
would add a few extra test/branches each time they're called --- not too worried
about that), but this is technically broken for every case that doesn't apply
arguments.

 }