[es6] Re-implement rest parameters via desugaring.

src/prettyprinter.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/prettyprinter.h"
 
 #include <stdarg.h>
 
 #include "src/ast-value-factory.h"
 #include "src/base/platform/platform.h"
@@ skipping 246 matching lines @@
   }
   Print("]");
 }
 
 
 void CallPrinter::VisitVariableProxy(VariableProxy* node) {
   PrintLiteral(node->name(), false);
 }
 
 
+void CallPrinter::VisitRestParameter(RestParameter* node) {
+  Print("...");
+  PrintLiteral(node->parameter()->name(), false);
+}
+
+
 void CallPrinter::VisitAssignment(Assignment* node) {
   Find(node->target());
   Find(node->value());
 }
 
 
 void CallPrinter::VisitYield(Yield* node) { Find(node->expression()); }
 
 
 void CallPrinter::VisitThrow(Throw* node) { Find(node->exception()); }
@@ skipping 465 matching lines @@
   }
   Print(" ]");
 }
 
 
 void PrettyPrinter::VisitVariableProxy(VariableProxy* node) {
   PrintLiteral(node->name(), false);
 }
 
 
+void PrettyPrinter::VisitRestParameter(RestParameter* node) {
+  Print("...");
+  PrintLiteral(node->parameter()->name(), false);
+}
+
+
 void PrettyPrinter::VisitAssignment(Assignment* node) {
   Visit(node->target());
   Print(" %s ", Token::String(node->op()));
   Visit(node->value());
 }
 
 
 void PrettyPrinter::VisitYield(Yield* node) {
   Print("yield ");
   Visit(node->expression());
@@ skipping 710 matching lines @@
       SNPrintF(buf + pos, " global[%d]", var->index());
       break;
     case VariableLocation::LOOKUP:
       SNPrintF(buf + pos, " lookup");
       break;
   }
   PrintLiteralWithModeIndented(buf.start(), var, node->name());
 }
 
 
+void AstPrinter::VisitRestParameter(RestParameter* node) {
+  Visit(node->parameter());
+}
+
+
 void AstPrinter::VisitAssignment(Assignment* node) {
   IndentedScope indent(this, Token::Name(node->op()));
   Visit(node->target());
   Visit(node->value());
 }
 
 
 void AstPrinter::VisitYield(Yield* node) {
   IndentedScope indent(this, "YIELD");
   Visit(node->expression());
@@ skipping 98 matching lines @@
 
 void AstPrinter::VisitSuperCallReference(SuperCallReference* node) {
   IndentedScope indent(this, "SUPER-CALL-REFERENCE");
 }
 
 
 #endif  // DEBUG
 
 }  // namespace internal
 }  // namespace v8