Add Riot logo via more targeted replacement

src/components/views/auth/VectorAuthHeaderLogo.js

@@ -0,0 +1,42 @@
+/*
+Copyright 2015, 2016 OpenMarket Ltd
+Copyright 2019 New Vector Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+'use strict';
+
+import React from 'react';
+import PropTypes from 'prop-types';
+
+const i = [1, 2, 3, 4, 5][Math.floor(Math.random() * 5)];
+const DEFAULT_LOGO_URI = "themes/riot/img/logos/riot-im-logo-" + i + ".svg";
+
+module.exports = React.createClass({
+    displayName: 'VectorAuthHeaderLogo',
+    statics: {
+        replaces: 'AuthHeaderLogo',
+    },
+    propTypes: {
+        icon: PropTypes.string,
+    },
+
+    render: function() {
+        return (
+            <div className="mx_AuthHeaderLogo">
+                <img src={this.props.icon || DEFAULT_LOGO_URI} alt="Riot" />
+            </div>
+        );
+    },
+});