Remove the rest_parameter(int*) variant, use rest_parameter() instead.

src/full-codegen/arm64/full-codegen-arm64.cc

Index: src/full-codegen/arm64/full-codegen-arm64.cc
diff --git a/src/full-codegen/arm64/full-codegen-arm64.cc b/src/full-codegen/arm64/full-codegen-arm64.cc
index 3330325df4447f152c9d133efe09c9526b47db3a..f859eabc381ed2a65284a08b921227630d5271ec 100644
--- a/src/full-codegen/arm64/full-codegen-arm64.cc
+++ b/src/full-codegen/arm64/full-codegen-arm64.cc
@@ -256,9 +256,8 @@ void FullCodeGenerator::Generate() {
   }
 
   // Possibly allocate RestParameters
-  int rest_index;
-  Variable* rest_param = info->scope()->rest_parameter(&rest_index);
-  if (rest_param) {
+  Variable* rest_param = info->scope()->rest_parameter();
+  if (rest_param != nullptr) {
     Comment cmnt(masm_, "[ Allocate rest parameter array");
     if (!function_in_register_x1) {
       __ Ldr(x1, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));