Diff ReactDOMFiber properties in prepareUpdate

We now take advantage of the new capability to diff properties early.
We do this by generating an update payload in the form of an array with
each property name and value that we're about to update.

Author: sebmarkbage

src/renderers/dom/fiber/ReactDOMFiber.js

@@ -35,6 +35,7 @@ var {
   createElement,
   getChildNamespace,
   setInitialProperties,
+  diffProperties,
   updateProperties,
 } = ReactDOMFiberComponent;
 var { precacheFiberNode } = ReactDOMComponentTree;
@@ -203,7 +204,7 @@ var DOMRenderer = ReactFiberReconciler({
     newProps : Props,
     rootContainerInstance : Container,
     hostContext : HostContext,
-  ) : null | Object {
+  ) : null | Array<mixed> {
     if (__DEV__) {
       const hostContextDev = ((hostContext : any) : HostContextDev);
       if (typeof newProps.children !== typeof oldProps.children && (
@@ -214,7 +215,7 @@ var DOMRenderer = ReactFiberReconciler({
         validateDOMNesting(null, String(newProps.children), null, ownAncestorInfo);
       }
     }
-    return {};
+    return diffProperties(domElement, type, oldProps, newProps, rootContainerInstance);
   },
 
   commitMount(
@@ -231,18 +232,17 @@ var DOMRenderer = ReactFiberReconciler({
 
   commitUpdate(
     domElement : Instance,
-    updatePayload : Object,
+    updatePayload : Array<mixed>,
     type : string,
     oldProps : Props,
     newProps : Props,
     internalInstanceHandle : Object,
   ) : void {
     // Update the internal instance handle so that we know which props are
     // the current ones.
-    // TODO: Fix this hack.
-    var rootContainerInstance = (domElement : any);
     precacheFiberNode(internalInstanceHandle, domElement);
-    updateProperties(domElement, type, oldProps, newProps, rootContainerInstance);
+    // Apply the diff to the DOM node.
+    updateProperties(domElement, updatePayload, type, oldProps, newProps);
   },
 
   shouldSetTextContent(props : Props) : boolean {