[stubs] Port NumberToString stub to TF

src/code-stubs-hydrogen.cc

Index: src/code-stubs-hydrogen.cc
diff --git a/src/code-stubs-hydrogen.cc b/src/code-stubs-hydrogen.cc
index a294d56c7a8592f8b49b69b78a1d844231155259..6c014c4dffee0ff83b6959c2527888da354cd0f6 100644
--- a/src/code-stubs-hydrogen.cc
+++ b/src/code-stubs-hydrogen.cc
@@ -328,18 +328,6 @@ static Handle<Code> DoGenerateCode(Stub* stub) {
 }
 
 
-template <>
-HValue* CodeStubGraphBuilder<NumberToStringStub>::BuildCodeStub() {
-  info()->MarkAsSavesCallerDoubles();
-  HValue* number = GetParameter(Descriptor::kArgument);
-  return BuildNumberToString(number, AstType::Number());
-}
-
-
-Handle<Code> NumberToStringStub::GenerateCode() {
-  return DoGenerateCode(this);
-}
-
 HValue* CodeStubGraphBuilderBase::BuildPushElement(HValue* object, HValue* argc,
                                                    HValue* argument_elements,
                                                    ElementsKind kind) {