core: Remove GcCell in MovieClip

Use field-wise interior mutability instead.

Author: moulins

core/src/avm1/activation.rs

@@ -729,7 +729,7 @@ impl<'a, 'gc> Activation<'a, 'gc> {
 
         if let Some((clip, frame)) = call_frame {
             if frame <= u16::MAX as u32 {
-                for action in clip.actions_on_frame(self.context, frame as u16) {
+                for action in clip.actions_on_frame(frame as u16) {
                     let _ = self.run_child_frame_for_action("[Frame Call]", clip.into(), action)?;
                 }
             }

core/src/avm1/globals/movie_clip.rs

@@ -987,7 +987,7 @@ pub fn clone_sprite<'gc>(
     new_clip.set_matrix(context.gc(), *movie_clip.base().matrix());
     new_clip.set_color_transform(context.gc(), *movie_clip.base().color_transform());
 
-    new_clip.set_clip_event_handlers(context.gc(), movie_clip.clip_actions().to_vec());
+    new_clip.set_clip_event_handlers((&*movie_clip.clip_actions()).into());
 
     if let Some(drawing) = movie_clip.drawing().as_deref().cloned() {
         *new_clip.drawing_mut(context.gc()) = drawing;

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

@@ -309,7 +309,7 @@ pub fn set_hit_area<'gc>(
         let object = args
             .try_get_object(activation, 0)
             .and_then(|hit_area| hit_area.as_display_object());
-        mc.set_hit_area(activation.context, object);
+        mc.set_hit_area(activation.gc(), object);
     }
 
     Ok(Value::Undefined)