Extract voice broadcast header (#9393)

res/css/_components.pcss

@@ -364,4 +364,5 @@
 @import "./views/voip/_PiPContainer.pcss";
 @import "./views/voip/_VideoFeed.pcss";
 @import "./voice-broadcast/atoms/_LiveBadge.pcss";
+@import "./voice-broadcast/atoms/_VoiceBroadcastHeader.pcss";
 @import "./voice-broadcast/molecules/_VoiceBroadcastRecordingBody.pcss";

res/css/components/atoms/_Icon.pcss

@@ -32,3 +32,7 @@ limitations under the License.
 .mx_Icon_live-badge {
     background-color: #fff;
 }
+
+.mx_Icon_compound-secondary-content {
+    background-color: $secondary-content;
+}

res/css/voice-broadcast/atoms/_VoiceBroadcastHeader.pcss

@@ -0,0 +1,44 @@
+/*
+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.
+*/
+
+.mx_VoiceBroadcastHeader {
+    align-items: flex-start;
+    display: flex;
+    gap: $spacing-8;
+    line-height: 20px;
+    margin-bottom: $spacing-8;
+    width: 266px;
+}
+
+.mx_VoiceBroadcastHeader_sender {
+    font-size: $font-12px;
+    font-weight: $font-semi-bold;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+}
+
+.mx_VoiceBroadcastHeader_room {
+    font-size: $font-12px;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+}
+
+.mx_VoiceBroadcastHeader_line {
+    align-items: center;
+    color: $secondary-content;
+    font-size: $font-12px;
+    display: flex;
+    gap: $spacing-4;
+}