[TreeView] Add TransitionProps support

Author: oliviertassinari

docs/pages/api/tree-item.md

@@ -33,6 +33,7 @@ You can learn more about the difference by [reading this guide](/guides/minimizi
 | <span class="prop-name">label</span> | <span class="prop-type">node</span> |  | The tree node label. |
 | <span class="prop-name required">nodeId&nbsp;*</span> | <span class="prop-type">string</span> |  | The id of the node. |
 | <span class="prop-name">TransitionComponent</span> | <span class="prop-type">elementType</span> | <span class="prop-default">Collapse</span> | The component used for the transition. [Follow this guide](/components/transitions/#transitioncomponent-prop) to learn more about the requirements for this component. |
+| <span class="prop-name">TransitionProps</span> | <span class="prop-type">object</span> |  | Props applied to the [`Transition`](http://reactcommunity.org/react-transition-group/transition#Transition-props) element. |
 
 The `ref` is forwarded to the root element.
 

packages/material-ui-lab/src/TreeItem/TreeItem.d.ts

@@ -33,6 +33,10 @@ export interface TreeItemProps
    * [Follow this guide](/components/transitions/#transitioncomponent-prop) to learn more about the requirements for this component.
    */
   TransitionComponent?: React.ComponentType<TransitionProps>;
+  /**
+   * Props applied to the [`Transition`](http://reactcommunity.org/react-transition-group/transition#Transition-props) element.
+   */
+  TransitionProps?: TransitionProps;
 }
 
 export type TreeItemClassKey =

packages/material-ui-lab/src/TreeItem/TreeItem.js

@@ -70,6 +70,7 @@ const TreeItem = React.forwardRef(function TreeItem(props, ref) {
     onFocus,
     onKeyDown,
     TransitionComponent = Collapse,
+    TransitionProps,
     ...other
   } = props;
 
@@ -298,6 +299,7 @@ const TreeItem = React.forwardRef(function TreeItem(props, ref) {
           in={expanded}
           component="ul"
           role="group"
+          {...TransitionProps}
         >
           {children}
         </TransitionComponent>
@@ -365,6 +367,10 @@ TreeItem.propTypes = {
    * [Follow this guide](/components/transitions/#transitioncomponent-prop) to learn more about the requirements for this component.
    */
   TransitionComponent: PropTypes.elementType,
+  /**
+   * Props applied to the [`Transition`](http://reactcommunity.org/react-transition-group/transition#Transition-props) element.
+   */
+  TransitionProps: PropTypes.object,
 };
 
 export default withStyles(styles, { name: 'MuiTreeItem' })(TreeItem);