[builtins] Migrate StringToNumber to TurboFan 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 708bc965d2e0ac6e70e1244bc1c60b8c28e9bd7d..54bc351f01e6f28d356923e0d7d68e49affd6017 100644
--- a/src/builtins/s390/builtins-s390.cc
+++ b/src/builtins/s390/builtins-s390.cc
@@ -2850,31 +2850,6 @@ void Builtins::Generate_Abort(MacroAssembler* masm) {
 }
 
 // static
-void Builtins::Generate_StringToNumber(MacroAssembler* masm) {
-  // The StringToNumber stub takes one argument in r2.
-  __ AssertString(r2);
-
-  // Check if string has a cached array index.
-  Label runtime;
-  __ LoadlW(r4, FieldMemOperand(r2, String::kHashFieldOffset));
-  __ And(r0, r4, Operand(String::kContainsCachedArrayIndexMask));
-  __ bne(&runtime);
-  __ IndexFromHash(r4, r2);
-  __ Ret();
-
-  __ bind(&runtime);
-  {
-    FrameScope frame(masm, StackFrame::INTERNAL);
-    // Push argument.
-    __ push(r2);
-    // We cannot use a tail call here because this builtin can also be called
-    // from wasm.
-    __ CallRuntime(Runtime::kStringToNumber);
-  }
-  __ Ret();
-}
-
-// static
 void Builtins::Generate_ToNumber(MacroAssembler* masm) {
   // The ToNumber stub takes one argument in r2.
   STATIC_ASSERT(kSmiTag == 0);