Replace sidebar header contents with call view during calls
Replace sidebar header contents with call view during calls

During calls the call view is now moved from the header actions to the
header itself, and all the other elements in the header (except the
close button) are hidden. This is done by setting a special CSS class,
"hidden-by-call", which is defined in a style sheet added dynamically.

When the file is changed the sidebar is cleared until the new file is
loaded. However, "setFileInfo" is called once the new file has loaded,
so the call view can not be hidden based on when a new fileInfo is set,
as that would keep the call view shown while the sidebar only shows the
loading spinner. However, "OCA.Talk.fileInfo" is cleared by
"FilesSidebarTab" when the tab is destroyed, which happens when the rest
of the sidebar is cleared, so that fileInfo is the one used to show and
hide the call view.

Signed-off-by: Daniel Calviño Sánchez <bd7629e975cc0e00ea7cda4ab6a120f2ee42ac1b@gmail.com>

nextcloud/spreed,nextcloud/spreed,nextcloud/spreed