Remove references to mx_GroupLayout from scss files (#8875)

res/css/views/elements/_EventTilePreview.scss

@@ -14,9 +14,6 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-.mx_EventTilePreview_loader {
-    &.mx_IRCLayout,
-    &.mx_GroupLayout {
-        padding: 9px 0;
-    }
+.mx_FontScalingPanel_fontSlider_preview.mx_EventTilePreview_loader {
+    padding: 9px 0;
 }

res/css/views/rooms/_ReadReceiptGroup.scss

@@ -21,7 +21,7 @@ limitations under the License.
     display: inline-block;
     // This aligns the avatar with the last line of the
     // message. We want to move it one line up
-    // See .mx_GroupLayout .mx_EventTile .mx_EventTile_line in _GroupLayout.scss
+    // See .mx_EventTile[data-layout=group] .mx_EventTile_line in _EventTile.scss
     top: calc(-$font-22px - 3px);
     user-select: none;
     z-index: 1;

src/components/views/elements/EventTilePreview.tsx

@@ -117,7 +117,6 @@ export default class EventTilePreview extends React.Component<IProps, IState> {
     public render() {
         const className = classnames(this.props.className, {
             "mx_IRCLayout": this.props.layout == Layout.IRC,
-            "mx_GroupLayout": this.props.layout == Layout.Group,
             "mx_EventTilePreview_loader": !this.props.userId,
         });
 

test/components/views/settings/__snapshots__/FontScalingPanel-test.tsx.snap

@@ -19,7 +19,7 @@ exports[`FontScalingPanel renders the font scaling UI 1`] = `
       userId={null}
     >
       <div
-        className="mx_FontScalingPanel_fontSlider_preview mx_GroupLayout mx_EventTilePreview_loader"
+        className="mx_FontScalingPanel_fontSlider_preview mx_EventTilePreview_loader"
       >
         <Spinner
           h={32}