message: replace TimePicker div wrapper with Fragment
diff: -import React, { Component } from 'react';
  +import React, { Component, Fragment } from 'react';
  import PropTypes from 'prop-types';
  import { withStyles } from 'material-ui';
  import PickerToolbar from '../_shared/PickerToolbar';
  @@ -73,7 +73,7 @@ export class TimePicker extends Component {
  : classes.hourMinuteLabel;
  return (
  - <div className={classes.container}>
  + <Fragment>
  <PickerToolbar className={classes.toolbar}>
  <div className={hourMinuteClassName}>
  <ToolbarButton
  @@ -139,8 +139,7 @@ export class TimePicker extends Component {
  utils={utils}
  />
  }
  - </div>
  -
  + </Fragment>
  );
  }
  }
  