New group call experience: Call tiles (#9332)

* Add call tiles

* Factor CallDuration out into a reusable component

* Correct the separator character in LiveContentSummary

src/components/views/rooms/LiveContentSummary.tsx

@@ -0,0 +1,57 @@
+/*
+Copyright 2022 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, { FC } from "react";
+import classNames from "classnames";
+
+import { _t } from "../../../languageHandler";
+
+export enum LiveContentType {
+    Video,
+    // More coming soon
+}
+
+interface Props {
+    type: LiveContentType;
+    text: string;
+    active: boolean;
+    participantCount: number;
+}
+
+/**
+ * Summary line used to call out live, interactive content such as calls.
+ */
+export const LiveContentSummary: FC<Props> = ({ type, text, active, participantCount }) => (
+    <span className="mx_LiveContentSummary">
+        <span
+            className={classNames("mx_LiveContentSummary_text", {
+                "mx_LiveContentSummary_text_video": type === LiveContentType.Video,
+                "mx_LiveContentSummary_text_active": active,
+            })}
+        >
+            { text }
+        </span>
+        { participantCount > 0 && <>
+            { " • " }
+            <span
+                className="mx_LiveContentSummary_participants"
+                aria-label={_t("%(count)s participants", { count: participantCount })}
+            >
+                { participantCount }
+            </span>
+        </> }
+    </span>
+);