Remember whether sidebar is shown for calls when switching rooms (#30262)

* Remember whether sidebar is shown for calls when switching rooms

Stores the sidebar state per-room in LegacyCallHandler, along with other details about calls.

* Hide the Show/Hide Sidebar from the Picture-in-Picture preview

The toggle sidebar button currently does nothing in PIP mode, since PIP mode never shows a sidebar (even when the call is made fullscreen from the PIP preview)

* Add test for Show/Hide Sidebar feature

* Add more tests for LegacyCallView and LegacyCallViewForRoom

Also, fix issue where LegacyCallViewForRoom used roomId and not callId for checking for sidebar state

src/components/structures/PipContainer.tsx

@@ -245,6 +245,7 @@ class PipContainerInner extends React.Component<IProps, IState> {
                     secondaryCall={this.state.secondaryCall}
                     pipMode={pipMode}
                     onResize={onResize}
+                    sidebarShown={false}
                 />
             ));
         }