Fiber HostConfig add getPublicInstance. This should be the identity fn everywhere except the test renderer

Author: iamdustan

src/renderers/art/ReactARTFiber.js

@@ -460,6 +460,10 @@ const ARTRenderer = ReactFiberReconciler({
     // Noop
   },
 
+  getPublicInstance(instance) {
+    return instance;
+  },
+
   insertBefore(parentInstance, child, beforeChild) {
     invariant(
       child !== beforeChild,

src/renderers/dom/fiber/ReactDOMFiber.js

@@ -123,6 +123,10 @@ var DOMRenderer = ReactFiberReconciler({
     return getChildNamespace(parentNamespace, type);
   },
 
+  getPublicInstance(instance) {
+    return instance;
+  },
+
   prepareForCommit() : void {
     eventsEnabled = ReactBrowserEventEmitter.isEnabled();
     ReactBrowserEventEmitter.setEnabled(false);

src/renderers/native/ReactNativeFiber.js

@@ -220,6 +220,10 @@ const NativeRenderer = ReactFiberReconciler({
     return emptyObject;
   },
 
+  getPublicInstance(instance) {
+    return instance;
+  },
+
   insertBefore(
     parentInstance : Instance | Container,
     child : Instance | TextInstance,

src/renderers/noop/ReactNoop.js

@@ -54,6 +54,10 @@ var NoopRenderer = ReactFiberReconciler({
     return emptyObject;
   },
 
+  getPublicInstance(instance) {
+    return instance;
+  },
+
   createInstance(type : string, props : Props) : Instance {
     const inst = {
       id: instanceCounter++,

src/renderers/shared/fiber/ReactFiberCommitWork.js

@@ -46,6 +46,7 @@ module.exports = function<T, P, I, TI, C, CX>(
     appendChild,
     insertBefore,
     removeChild,
+    getPublicInstance,
   } = config;
 
   const {
@@ -86,11 +87,7 @@ module.exports = function<T, P, I, TI, C, CX>(
   function attachRef(current : ?Fiber, finishedWork : Fiber, instance : any) {
     const ref = finishedWork.ref;
     if (ref && (!current || current.ref !== ref)) {
-      if (typeof config.getPublicInstance === 'function') {
-        ref(config.getPublicInstance(instance));
-      } else {
-        ref(instance);
-      }
+      ref(getPublicInstance(instance));
     }
   }