Support for room upgrades

* Show when a room upgrade is needed
 * Dialog box to perform the upgrade

src/components/views/dialogs/RoomUpgradeDialog.js

@@ -0,0 +1,106 @@
+/*
+Copyright 2018 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.
+*/
+
+import React from 'react';
+import PropTypes from 'prop-types';
+import sdk from '../../../index';
+import MatrixClientPeg from '../../../MatrixClientPeg';
+import Modal from '../../../Modal';
+import { _t } from '../../../languageHandler';
+
+export default React.createClass({
+    displayName: 'RoomUpgradeDialog',
+
+    propTypes: {
+        room: PropTypes.object.isRequired,
+        onFinished: PropTypes.func.isRequired,
+    },
+
+    componentWillMount: function() {
+        this._targetVersion = this.props.room.shouldUpgradeToVersion();
+    },
+
+    getInitialState: function() {
+        return {
+            busy: false,
+        };
+    },
+
+    _onCancelClick: function() {
+        this.props.onFinished(false);
+    },
+
+    _onUpgradeClick: function() {
+        this.setState({busy: true});
+        MatrixClientPeg.get().upgradeRoom(this.props.room.roomId, this._targetVersion).catch((err) => {
+            const ErrorDialog = sdk.getComponent("dialogs.ErrorDialog");
+            Modal.createTrackedDialog('Failed to upgrade room', '', ErrorDialog, {
+                title: _t("Failed to upgrade room"),
+                description: ((err && err.message) ? err.message : _t("The room upgrade could not be completed")),
+            });
+        }).finally(() => {
+            this.setState({busy: false});
+        });
+    },
+
+    render: function() {
+        const BaseDialog = sdk.getComponent('views.dialogs.BaseDialog');
+        const DialogButtons = sdk.getComponent('views.elements.DialogButtons');
+        const Spinner = sdk.getComponent('views.elements.Spinner');
+
+        let buttons;
+        if (this.state.busy) {
+            buttons = <Spinner />;
+        } else {
+            buttons = <DialogButtons
+                primaryButton={_t(
+                    'Upgrade this room to version %(version)s',
+                    {version: this._targetVersion},
+                )}
+                primaryButtonClass="danger"
+                hasCancel={true}
+                onPrimaryButtonClick={this._onUpgradeClick}
+                focus={this.props.focus}
+                onCancel={this._onCancelClick}
+            />;
+        }
+
+        return (
+            <BaseDialog className="mx_RoomUpgradeDialog"
+                onFinished={this.onCancelled}
+                title={_t("Upgrade Room Version")}
+                contentId='mx_Dialog_content'
+                onFinished={this.props.onFinished}
+                hasCancel={true}
+            >
+                <p>
+                    {_t(
+                        "Upgrading this room requires closing down the current " +
+                        "instance of the room and creating a new room it its place. " +
+                        "To give room members the best possible experience, we will:",
+                    )}
+                </p>
+                <ol>
+                    <li>{_t("Create a new room with the same name, description and avatar")}</li>
+                    <li>{_t("Update any local room aliases to point to the new room")}</li>
+                    <li>{_t("Stop users from speaking in the old version of the room, and post a message advising users to move to the new room")}</li>
+                    <li>{_t("Put a link back to the old room at the start of the new room so people can see old messages")}</li>
+                </ol>
+                {buttons}
+            </BaseDialog>
+        );
+    },
+});