Implement ES6 rest parameters

src/compiler.cc

Index: src/compiler.cc
diff --git a/src/compiler.cc b/src/compiler.cc
index e9cc11172664b92470eb0a9d0c530b4cbd3e303f..378db944aac555d76565b09c02261a4f35631b1b 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -312,6 +312,11 @@ void CompilationInfo::EnsureFeedbackVector() {
 }
 
 
+bool CompilationInfo::is_simple_parameter_list() {
+  return scope_->is_simple_parameter_list();
+}
+
+
 class HOptimizedGraphBuilderWithPositions: public HOptimizedGraphBuilder {
  public:
   explicit HOptimizedGraphBuilderWithPositions(CompilationInfo* info)
@@ -618,7 +623,7 @@ static void SetFunctionInfo(Handle<SharedFunctionInfo> function_info,
                             FunctionLiteral* lit,
                             bool is_toplevel,
                             Handle<Script> script) {
-  function_info->set_length(lit->parameter_count());
+  function_info->set_length(lit->scope()->default_function_length());
   function_info->set_formal_parameter_count(lit->parameter_count());
   function_info->set_script(*script);
   function_info->set_function_token_position(lit->function_token_position());