Fix missing conversion of optional arguments of components.

This was done for normal calls in ee6bda7, but not for components.

Author: cristianoc

examples/flow-react-example/src/components/ManyComponents.bs.js

@@ -5,6 +5,8 @@
  */
 /* eslint-disable */
 
+const $$toRE312434514 = {"Small": 0, "Medium": 1, "Large": 2};
+
 // $FlowExpectedError: Reason checked type sufficiently
 import * as Curry from 'bs-platform/lib/es6/curry.js';
 
@@ -14,6 +16,8 @@ import * as ManyComponentsBS from './ManyComponents.bs';
 // $FlowExpectedError: Reason checked type sufficiently
 import * as ReasonReact from 'reason-react/src/ReasonReact.js';
 
+export type size = "Small" | "Medium" | "Large";
+
 export type InnerComponent_Props = {| +children?: mixed |};
 
 export const InnerComponent: React$ComponentType<InnerComponent_Props> = ReasonReact.wrapReasonForJs(
@@ -40,12 +44,12 @@ export const ManyProps: React$ComponentType<ManyProps_Props> = ReasonReact.wrapR
      return Curry.app(ManyComponentsBS.ManyProps[1], [jsProps.a, jsProps.b, jsProps.c, jsProps.d, jsProps.e, jsProps.f, jsProps.g, jsProps.h, jsProps.children]);
   }));
 
-export type Props = {| +children?: mixed |};
+export type Props = {| +size?: size, +children?: mixed |};
 
 export const component: React$ComponentType<Props> = ReasonReact.wrapReasonForJs(
   ManyComponentsBS.component,
   (function _(jsProps: Props) {
-     return ManyComponentsBS.make(jsProps.children);
+     return Curry._2(ManyComponentsBS.make, (jsProps.size == null ? undefined : $$toRE312434514[jsProps.size]), jsProps.children);
   }));
 
 export default component;

examples/flow-react-example/src/components/ManyComponents.gen.js

@@ -31,10 +31,16 @@ module ManyProps = {
   };
 };
 
+[@genType]
+type size =
+  | Small
+  | Medium
+  | Large;
+
 let component = ReasonReact.statelessComponent("ManyComponents");
 
 [@genType]
-let make = _children => {
+let make = (~size as _=Small, _children) => {
   ...component,
   render: _ =>
     <div> "Outer Component"->ReasonReact.string <InnerComponent /> </div>,

examples/flow-react-example/src/components/ManyComponents.re

@@ -509,11 +509,17 @@ let rec emitCodeItem =
           ] =>
           (
             propConverters
-            |> List.map(((s, _optional, argConverter)) =>
+            |> List.map(((s, optional, argConverter)) =>
                  jsPropsDot(s)
                  |> Converter.toReason(
                       ~config,
-                      ~converter=argConverter,
+                      ~converter=
+                        optional == Optional
+                        && !(
+                             argConverter
+                             |> Converter.converterIsIdentity(~toJS=false)
+                           ) ?
+                          OptionC(argConverter) : argConverter,
                       ~indent,
                       ~nameGen,
                       ~useCreateBucklescriptBlock,