room-details: Allow to toggle fullscreen for MediaViewer

data/resources/style.css

@@ -146,7 +146,7 @@ power-level-badge.mod {
   background-color: @warning_bg_color;
 }
 
-media-viewer headerbar {
+media-viewer toolbarview headerbar {
   background: black;
   color: white;
 }

src/session/view/content/room_details/mod.rs

@@ -75,6 +75,14 @@ mod imp {
                     widget.show_subpage(subpage, false);
                 },
             );
+
+            klass.install_action("win.toggle-fullscreen", None, |obj, _, _| {
+                if obj.is_fullscreened() {
+                    obj.unfullscreen();
+                } else {
+                    obj.fullscreen();
+                }
+            });
         }
 
         fn instance_init(obj: &InitializingObject<Self>) {

src/session/view/media_viewer.rs

@@ -11,7 +11,6 @@ use crate::{
     session::model::Room,
     spawn, toast,
     utils::{matrix::get_media_content, media::save_to_file},
-    Window,
 };
 
 const ANIMATION_DURATION: u32 = 250;
@@ -171,7 +170,7 @@ mod imp {
 
             // Bind `fullscreened` to the window property of the same name.
             obj.connect_root_notify(|obj| {
-                if let Some(window) = obj.root().and_downcast::<Window>() {
+                if let Some(window) = obj.root().and_downcast::<gtk::Window>() {
                     window
                         .bind_property("fullscreened", obj, "fullscreened")
                         .sync_create()