[es6] support rest parameters in arrow functions

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 1345a790eb6258d0d0d6d6bdc5bfb95778ac42e8..aa101a8a2a46d1ab89879cf9eb18a9cf6d76913e 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -3553,6 +3553,11 @@ bool CheckAndDeclareArrowParameter(ParserTraits* traits, Expression* expression,
   // Case for a single parameter:
   //   (foo) => ...
   //   foo => ...
+  bool is_rest = false;

[arv (Not doing code reviews), 2015/03/10 13:44:02]

Maybe this should go after the IsVariableProxy check since the comment above is
about that.

Or at least update the comment.

+  if (expression->IsSpreadOperation()) {
+    expression = expression->AsSpreadOperation()->expression();
+    is_rest = true;
+  }
   if (expression->IsVariableProxy()) {
     if (expression->AsVariableProxy()->is_this()) return false;
 
@@ -3567,7 +3572,7 @@ bool CheckAndDeclareArrowParameter(ParserTraits* traits, Expression* expression,
       return false;
     }
 
-    scope->DeclareParameter(raw_name, VAR);
+    scope->DeclareParameter(raw_name, VAR, is_rest);
     ++(*num_params);
     return true;
   }