Verification nag toasts

Implement the three differenty cases for this session, and also fix
ones for other sessions which had the wrong copy.

Fixes https://github.com/vector-im/riot-web/issues/11220

src/components/views/toasts/SetupEncryptionToast.js

@@ -0,0 +1,68 @@
+/*
+Copyright 2020 The Matrix.org Foundation C.I.C.
+
+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 * as sdk from "../../../index";
+import { _t } from '../../../languageHandler';
+import DeviceListener from '../../../DeviceListener';
+import { accessSecretStorage } from '../../../CrossSigningManager';
+
+export default class SetupEncryptionToast extends React.PureComponent {
+    static propTypes = {
+        toastKey: PropTypes.string.isRequired,
+        kind: PropTypes.oneOf(['set_up_encryption', 'verify_this_session', 'upgrade_encryption']).isRequired,
+    };
+
+    _onLaterClick = () => {
+        DeviceListener.sharedInstance().dismissEncryptionSetup();
+    };
+
+    _onSetupClick = async () => {
+        accessSecretStorage();
+    };
+
+    getDescription() {
+        switch (this.props.kind) {
+            case 'set_up_encryption':
+            case 'upgrade_encryption':
+                return _t('Verify your other devices easier');
+            case 'verify_this_session':
+                return _t('Other users may not trust it');
+        }
+    }
+
+    getSetupCaption() {
+        switch (this.props.kind) {
+            case 'set_up_encryption':
+            case 'upgrade_encryption':
+                return _t('Upgrade');
+            case 'verify_this_session':
+                return _t('Verify');
+        }
+    }
+
+    render() {
+        const FormButton = sdk.getComponent("elements.FormButton");
+        return (<div>
+            <div className="mx_Toast_description">{this.getDescription()}</div>
+            <div className="mx_Toast_buttons" aria-live="off">
+                <FormButton label={_t("Later")} kind="danger" onClick={this._onLaterClick} />
+                <FormButton label={this.getSetupCaption()} onClick={this._onSetupClick} />
+            </div>
+        </div>);
+    }
+}