Delegate to ProgressBarAndroid from ActivityIndicator on Android, instead of the other way around

Summary:
`ProgressBarAndroid` regressed after fixing a bug in ccddbf82d7

Run this gist on a new project with this code: https://gist.github.com/brentvatne/a0b57e5bbae1bd2cf76765ea27f077af

Notice that you will see:

<img width="642" alt="screen shot 2017-10-17 at 11 06 03 am" src="https://user-images.githubusercontent.com/90494/31681142-3437a95a-b32b-11e7-85d3-c29bfbfe591e.png">

hmmm... doesn't seem right �

With the patch in this PR applied, you will see:

<img width="642" alt="screen shot 2017-10-17 at 11 01 38 am" src="https://user-images.githubusercontent.com/90494/31680950-b0c1805a-b32a-11e7-909e-42cdf478da56.png">

oh! there we go 😄

[ANDROID] [BUGFIX] [ProgressBarAndroid] - Fix regression in ProgressBarAndroid which limited `styleAttr` to only `Regular`.
Closes https://github.com/facebook/react-native/pull/16435

Differential Revision: D6080118

Pulled By: hramos

fbshipit-source-id: 537ee2c96deedd7b2e75ff3dbdefc1506812f3f3

Libraries/Components/ProgressBarAndroid/ProgressBarAndroid.android.js

@@ -17,6 +17,8 @@ const React = require('React');
 const ReactNative = require('ReactNative');
 const ViewPropTypes = require('ViewPropTypes');
 
+const requireNativeComponent = require('requireNativeComponent');
+
 const STYLE_ATTRIBUTES = [
   'Horizontal',
   'Normal',
@@ -78,6 +80,10 @@ class ProgressBarAndroid extends ReactNative.NativeComponent {
      * - LargeInverse
      */
     styleAttr: PropTypes.oneOf(STYLE_ATTRIBUTES),
+    /**
+     * Whether to show the ProgressBar (true, the default) or hide it (false).
+     */
+    animating: PropTypes.bool,
     /**
      * If the progress bar will show indeterminate progress. Note that this
      * can only be false if styleAttr is Horizontal.
@@ -99,7 +105,8 @@ class ProgressBarAndroid extends ReactNative.NativeComponent {
 
   static defaultProps = {
     styleAttr: 'Normal',
-    indeterminate: true
+    indeterminate: true,
+    animating: true,
   };
 
   componentDidMount() {
@@ -112,8 +119,18 @@ class ProgressBarAndroid extends ReactNative.NativeComponent {
   }
 
   render() {
-    return <ActivityIndicator {...this.props} animating={true} />;
+    return <AndroidProgressBar {...this.props} />;
   }
 }
 
+const AndroidProgressBar = requireNativeComponent(
+  'AndroidProgressBar',
+  ProgressBarAndroid,
+  {
+    nativeOnly: {
+      animating: true,
+    },
+  }
+);
+
 module.exports = ProgressBarAndroid;