[runtime] Optimize and unify rest parameters.

src/code-stubs.cc

Index: src/code-stubs.cc
diff --git a/src/code-stubs.cc b/src/code-stubs.cc
index 02d573b89cffb440d54cb07fae2a2f33738fc3ec..6f03f300b67f59898fadc165663c6dec73d27355 100644
--- a/src/code-stubs.cc
+++ b/src/code-stubs.cc
@@ -822,9 +822,6 @@ void StoreFastElementStub::GenerateAheadOfTime(Isolate* isolate) {
 }
 
 
-void RestParamAccessStub::Generate(MacroAssembler* masm) { GenerateNew(masm); }
-
-
 void ArgumentsAccessStub::Generate(MacroAssembler* masm) {
   switch (type()) {
     case READ_ELEMENT:
@@ -863,11 +860,6 @@ void ArgumentsAccessStub::PrintName(std::ostream& os) const {  // NOLINT
 }
 
 
-void RestParamAccessStub::PrintName(std::ostream& os) const {  // NOLINT
-  os << "RestParamAccessStub_";
-}
-
-
 void ArrayConstructorStub::PrintName(std::ostream& os) const {  // NOLINT
   os << "ArrayConstructorStub";
   switch (argument_count()) {