[stubs] replaced ToString MacroAssembler Stub with CodeStubAssembler builtin

src/builtins/s390/builtins-s390.cc

Index: src/builtins/s390/builtins-s390.cc
diff --git a/src/builtins/s390/builtins-s390.cc b/src/builtins/s390/builtins-s390.cc
index 1b4cfaa6ca36f967524c107e77d8d3127100b5f6..d140427ed760b243d21499fd5e70cd08224853ec 100644
--- a/src/builtins/s390/builtins-s390.cc
+++ b/src/builtins/s390/builtins-s390.cc
@@ -396,10 +396,9 @@ void Builtins::Generate_StringConstructor(MacroAssembler* masm) {
   __ bind(&to_string);
   {
     FrameScope scope(masm, StackFrame::MANUAL);
-    ToStringStub stub(masm->isolate());
     __ SmiTag(r4);
     __ EnterBuiltinFrame(cp, r3, r4);
-    __ CallStub(&stub);
+    __ Call(masm->isolate()->builtins()->ToString(), RelocInfo::CODE_TARGET);
     __ LeaveBuiltinFrame(cp, r3, r4);
     __ SmiUntag(r4);
   }
@@ -459,12 +458,11 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ bind(&convert);
     {
       FrameScope scope(masm, StackFrame::MANUAL);
-      ToStringStub stub(masm->isolate());
       __ SmiTag(r8);
       __ EnterBuiltinFrame(cp, r3, r8);
       __ Push(r5);
       __ LoadRR(r2, r4);
-      __ CallStub(&stub);
+      __ Call(masm->isolate()->builtins()->ToString(), RelocInfo::CODE_TARGET);
       __ LoadRR(r4, r2);
       __ Pop(r5);
       __ LeaveBuiltinFrame(cp, r3, r8);