[ReactNative] Text docs

Summary:
In preparation for open sourcing React Native for Android, document which Text props are platform-specific.

Libraries/Text/Text.js

@@ -74,19 +74,24 @@ var Text = React.createClass({
   propTypes: {
     /**
      * Used to truncate the text with an elipsis after computing the text
-     * layout, including line wrapping, such that the total number of lines does
-     * not exceed this number.
+     * layout, including line wrapping, such that the total number of lines
+     * does not exceed this number.
      */
     numberOfLines: React.PropTypes.number,
     /**
-     * This function is called on press.  Text intrinsically supports press
-     * handling with a default highlight state (which can be disabled with
-     * `suppressHighlighting`).
+     * Invoked on mount and layout changes with
+     *
+     *   `{nativeEvent: {layout: {x, y, width, height}}}`
+     */
+    onLayout: React.PropTypes.func,
+    /**
+     * This function is called on press.
      */
     onPress: React.PropTypes.func,
     /**
-     * When true, no visual change is made when text is pressed down.  By
+     * When true, no visual change is made when text is pressed down. By
      * default, a gray oval highlights the text on press down.
+     * @platform ios
      */
     suppressHighlighting: React.PropTypes.bool,
     style: stylePropType,
@@ -94,12 +99,6 @@ var Text = React.createClass({
      * Used to locate this view in end-to-end tests.
      */
     testID: React.PropTypes.string,
-    /**
-     * Invoked on mount and layout changes with
-     *
-     *   {nativeEvent: {layout: {x, y, width, height}}}.
-     */
-     onLayout: React.PropTypes.func,
   },
 
   viewConfig: viewConfig,