Move desugaring of super calls with trailing spread to one runtime call.

src/ast/ast-numbering.cc

Index: src/ast/ast-numbering.cc
diff --git a/src/ast/ast-numbering.cc b/src/ast/ast-numbering.cc
index c422744c6cc95f38f61f5f2e38ac4e021dc091b5..9d44fdbb21f842aadfc3ba3f16d00da2788dec39 100644
--- a/src/ast/ast-numbering.cc
+++ b/src/ast/ast-numbering.cc
@@ -394,9 +394,11 @@ void AstNumberingVisitor::VisitCompareOperation(CompareOperation* node) {
   ReserveFeedbackSlots(node);
 }
 
-
-void AstNumberingVisitor::VisitSpread(Spread* node) { UNREACHABLE(); }
-
+void AstNumberingVisitor::VisitSpread(Spread* node) {
+  IncrementNodeCount();

[rmcilroy, 2016/11/30 14:35:32]

I think this should this disable Fullcodegen and Crankshaft
(DisableFullCodegenAndCrankshaft) since we only have bytecode graph builder
implementations of it?

[petermarshall, 2016/11/30 15:24:48]

I think we are technically safe because a spread only shows up in the AST as a
child of a SuperCallReference, which disables them already, although we don't
have a way for the type system or DCHECKs to enforce this so it could break
weirdly in the future. I disabled it here anyway and left a comment.

[rmcilroy, 2016/11/30 15:45:04]

Ahh makes sense, thanks.

+  node->set_base_id(ReserveIdRange(Spread::num_ids()));
+  Visit(node->expression());
+}
 
 void AstNumberingVisitor::VisitEmptyParentheses(EmptyParentheses* node) {
   UNREACHABLE();