ref: remove unused code

react/features/toolbox/components/native/Toolbox.js

 // @flow
 
-import React, { Component } from 'react';
+import React, { PureComponent } from 'react';
 import { View } from 'react-native';
 
 import { ColorSchemeRegistry } from '../../../base/color-scheme';
     dispatch: Function
 };
 
-/**
- * The type of {@link Toolbox}'s React {@code Component} state.
- */
-type State = {
-
-    /**
-     * The detected width for this component.
-     */
-    width: number
-};
-
 /**
  * Implements the conference toolbox on React Native.
  */
-class Toolbox extends Component<Props, State> {
-    state = {
-        width: 0
-    };
-
-    /**
-     *  Initializes a new {@code Toolbox} instance.
-     *
-     * @inheritdoc
-     */
-    constructor(props: Props) {
-        super(props);
-
-        // Bind event handlers so they are only bound once per instance.
-        this._onLayout = this._onLayout.bind(this);
-    }
-
+class Toolbox extends PureComponent<Props> {
     /**
      * Implements React's {@link Component#render()}.
      *
     render() {
         return (
             <Container
-                onLayout = { this._onLayout }
                 style = { styles.toolbox }
                 visible = { this.props._visible }>
                 { this._renderToolbar() }
         };
     }
 
-    _onLayout: (Object) => void;
-
-    /**
-     * Handles the "on layout" View's event and stores the width as state.
-     *
-     * @param {Object} event - The "on layout" event object/structure passed
-     * by react-native.
-     * @private
-     * @returns {void}
-     */
-    _onLayout({ nativeEvent: { layout: { width } } }) {
-        this.setState({ width });
-    }
-
     /**
      * Renders the toolbar. In order to avoid a weird visual effect in which the
      * toolbar is (visually) rendered and then visibly changes its size, it is