Remove arguments shadow from scopes, stop rewriting parameters.

arguments/src/arm/codegen-arm.cc

Index: arguments/src/arm/codegen-arm.cc
diff --git a/arguments/src/arm/codegen-arm.cc b/arguments/src/arm/codegen-arm.cc
index 364f65262d0c5a65a8a443747d6986c6c1674073..04a46a0a22f4d789a58e31b4c81643d1530645a2 100644
--- a/arguments/src/arm/codegen-arm.cc
+++ b/arguments/src/arm/codegen-arm.cc
@@ -578,8 +578,6 @@ void CodeGenerator::LoadGlobalReceiver(Register scratch) {
 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.
@@ -615,10 +613,7 @@ void 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;
   if (mode == LAZY_ARGUMENTS_ALLOCATION && !initial) {
@@ -633,9 +628,6 @@ void 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);
-  }
 }