core: Drop the focus when it's made invisible

When an object has focus and is made invisible,
the focus should be dropped.

core/src/avm1/object/stage_object.rs

@@ -592,7 +592,7 @@ fn set_visible<'gc>(
     // Because this property dates to the era of Flash 4, this is actually coerced to an integer.
     // `_visible = "false";` coerces to NaN and has no effect.
     if let Some(n) = property_coerce_to_number(activation, val)? {
-        this.set_visible(activation.context.gc_context, n != 0.0);
+        this.set_visible(&mut activation.context, n != 0.0);
     }
     Ok(())
 }

core/src/avm2/globals/flash/display/display_object.rs

@@ -617,7 +617,7 @@ pub fn set_visible<'gc>(
     if let Some(dobj) = this.as_display_object() {
         let new_visible = args.get_bool(0);
 
-        dobj.set_visible(activation.context.gc_context, new_visible);
+        dobj.set_visible(&mut activation.context, new_visible);
     }
 
     Ok(Value::Undefined)

core/src/debug_ui/display_object.rs

@@ -700,7 +700,7 @@ impl DisplayObjectWindow {
                 ui.checkbox(&mut is_visible, "Visible");
                 ui.end_row();
                 if is_visible != was_visible {
-                    object.set_visible(context.gc_context, is_visible);
+                    object.set_visible(context, is_visible);
                 }
 
                 ui.label("Blend mode");

core/src/display_object.rs

@@ -1738,11 +1738,18 @@ pub trait TDisplayObject<'gc>:
     /// Sets whether this display object will be visible.
     /// Invisible objects are not rendered, but otherwise continue to exist normally.
     /// Returned by the `_visible`/`visible` ActionScript properties.
-    fn set_visible(&self, gc_context: &Mutation<'gc>, value: bool) {
-        if self.base_mut(gc_context).set_visible(value) {
+    fn set_visible(&self, context: &mut UpdateContext<'_, 'gc>, value: bool) {
+        if self.base_mut(context.gc()).set_visible(value) {
             if let Some(parent) = self.parent() {
                 // We don't need to invalidate ourselves, we're just toggling if the bitmap is rendered.
-                parent.invalidate_cached_bitmap(gc_context);
+                parent.invalidate_cached_bitmap(context.gc());
+            }
+        }
+
+        if !value {
+            if let Some(int) = self.as_interactive() {
+                // The object's focus is dropped when it's made invisible.
+                int.drop_focus(context);
             }
         }
     }
@@ -2209,7 +2216,7 @@ pub trait TDisplayObject<'gc>:
             }
             if self.swf_version() >= 11 {
                 if let Some(visible) = place_object.is_visible {
-                    self.set_visible(context.gc_context, visible);
+                    self.set_visible(context, visible);
                 }
                 if let Some(mut color) = place_object.background_color {
                     let color = if color.a > 0 {

core/src/player.rs

@@ -1292,14 +1292,14 @@ impl Player {
                 // Turn the dragged object invisible so that we don't pick it.
                 // TODO: This could be handled via adding a `HitTestOptions::SKIP_DRAGGED`.
                 let was_visible = display_object.visible();
-                display_object.set_visible(context.gc_context, false);
+                display_object.set_visible(context, false);
                 // Set `_droptarget` to the object the mouse is hovering over.
                 let drop_target_object = run_mouse_pick(context, false);
                 movie_clip.set_drop_target(
                     context.gc_context,
                     drop_target_object.map(|d| d.as_displayobject()),
                 );
-                display_object.set_visible(context.gc_context, was_visible);
+                display_object.set_visible(context, was_visible);
             }
         }
     }