Remove arguments shadow from scopes, stop rewriting parameters.

arguments/src/ia32/codegen-ia32.cc

Index: arguments/src/ia32/codegen-ia32.cc
diff --git a/arguments/src/ia32/codegen-ia32.cc b/arguments/src/ia32/codegen-ia32.cc
index f1d4cac19178272dac1b5760f6b1a8cc20d66ace..3cf79822f8c0fd07425fe80882c72fd6664c91b6 100644
--- a/arguments/src/ia32/codegen-ia32.cc
+++ b/arguments/src/ia32/codegen-ia32.cc
@@ -730,9 +730,6 @@ void CodeGenerator::LoadTypeofExpression(Expression* expr) {
 ArgumentsAllocationMode CodeGenerator::ArgumentsMode() {
   if (scope()->arguments() == NULL) return NO_ARGUMENTS_ALLOCATION;
 
-  // In strict mode there is no need for shadow arguments.
-  ASSERT(scope()->arguments_shadow() != NULL || scope()->is_strict_mode());
-
   // We don't want to do lazy arguments allocation for functions that
   // have heap-allocated contexts, because it interfers with the
   // uninitialized const tracking in the context objects.
@@ -762,11 +759,7 @@ Result CodeGenerator::StoreArgumentsObject(bool initial) {
   }
 
   Variable* arguments = scope()->arguments();
-  Variable* shadow = scope()->arguments_shadow();
-
   ASSERT(arguments != NULL && arguments->AsSlot() != NULL);
-  ASSERT((shadow != NULL && shadow->AsSlot() != NULL) ||
-         scope()->is_strict_mode());
 
   JumpTarget done;
   bool skip_arguments = false;
@@ -790,9 +783,6 @@ Result CodeGenerator::StoreArgumentsObject(bool initial) {
     StoreToSlot(arguments->AsSlot(), NOT_CONST_INIT);
     if (mode == LAZY_ARGUMENTS_ALLOCATION) done.Bind();
   }
-  if (shadow != NULL) {
-    StoreToSlot(shadow->AsSlot(), NOT_CONST_INIT);
-  }
   return frame_->Pop();
 }