[Interpreter] Introduce IncStub and DecStub.

src/code-factory.cc

Index: src/code-factory.cc
diff --git a/src/code-factory.cc b/src/code-factory.cc
index b4f786ddb959df56ecac24ca140ad70e876fddcf..177cacb63c621e389917941d09fc9c71407fae2f 100644
--- a/src/code-factory.cc
+++ b/src/code-factory.cc
@@ -281,6 +281,18 @@ Callable CodeFactory::BitwiseXor(Isolate* isolate) {
 }
 
 // static
+Callable CodeFactory::Inc(Isolate* isolate) {
+  IncStub stub(isolate);
+  return Callable(stub.GetCode(), stub.GetCallInterfaceDescriptor());
+}
+
+// static
+Callable CodeFactory::Dec(Isolate* isolate) {
+  DecStub stub(isolate);
+  return Callable(stub.GetCode(), stub.GetCallInterfaceDescriptor());
+}
+
+// static
 Callable CodeFactory::LessThan(Isolate* isolate) {
   LessThanStub stub(isolate);
   return Callable(stub.GetCode(), stub.GetCallInterfaceDescriptor());