Add method to Modal to create dialog with instantiated React elements as well as Classes.

src/controllers/molecules/ChangeAvatar.js

@@ -19,7 +19,6 @@ var MatrixClientPeg = require("../../MatrixClientPeg");
 
 module.exports = {
     propTypes: {
-        onFinished: React.PropTypes.func,
         initialAvatarUrl: React.PropTypes.string.isRequired,
     },
 
@@ -29,12 +28,6 @@ module.exports = {
         Error: "error",
     },
 
-    getDefaultProps: function() {
-        return {
-            onFinished: function() {},
-        };
-    },
-
     getInitialState: function() {
         return {
             avatarUrl: this.props.initialAvatarUrl,