core: Remove some manual `Collect` impls

Some were completely unused, while others could be replaced
with a `#[derive(Collect)]`

core/src/avm1/activation.rs

@@ -171,15 +171,6 @@ impl<'a> ActivationIdentifier<'a> {
     }
 }
 
-unsafe impl<'gc> gc_arena::Collect for ActivationIdentifier<'gc> {
-    fn needs_trace() -> bool {
-        false
-    }
-
-    #[inline]
-    fn trace(&self, _cc: gc_arena::CollectionContext) {}
-}
-
 pub struct Activation<'a, 'gc: 'a, 'gc_context: 'a> {
     /// Represents the SWF version of a given function.
     ///

core/src/avm1/function.rs

@@ -10,7 +10,7 @@ use crate::avm1::{ArrayObject, Object, ObjectPtr, ScriptObject, TObject};
 use crate::display_object::{DisplayObject, TDisplayObject};
 use crate::string::AvmString;
 use crate::tag_utils::SwfSlice;
-use gc_arena::{Collect, CollectionContext, Gc, GcCell, MutationContext};
+use gc_arena::{Collect, Gc, GcCell, MutationContext};
 use std::{borrow::Cow, fmt, num::NonZeroU8};
 use swf::{avm1::types::FunctionFlags, SwfStr};
 
@@ -290,25 +290,17 @@ struct Param<'gc> {
 
 /// Represents a function that can be defined in the Ruffle runtime or by the
 /// AVM1 bytecode itself.
-#[derive(Clone)]
+#[derive(Clone, Collect)]
+#[collect(no_drop)]
 pub enum Executable<'gc> {
     /// A function provided by the Ruffle runtime and implemented in Rust.
-    Native(NativeFunction),
+    Native(#[collect(require_static)] NativeFunction),
 
     /// ActionScript data defined by a previous `DefineFunction` or
     /// `DefineFunction2` action.
     Action(Gc<'gc, Avm1Function<'gc>>),
 }
 
-unsafe impl<'gc> Collect for Executable<'gc> {
-    fn trace(&self, cc: CollectionContext) {
-        match self {
-            Self::Native(_) => {}
-            Self::Action(af) => af.trace(cc),
-        }
-    }
-}
-
 impl fmt::Debug for Executable<'_> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match self {

core/src/avm1/object/stage_object.rs

@@ -345,18 +345,22 @@ impl<'gc> TObject<'gc> for StageObject<'gc> {
 /// "special" properties stored in a separate map that display objects look at in addition
 /// to normal property lookup.
 /// The map of property names to display object getts/setters.
-#[derive(Copy, Clone)]
-pub struct DisplayProperty<'gc> {
-    get: DisplayGetter<'gc>,
-    set: Option<DisplaySetter<'gc>>,
+#[derive(Copy, Clone, Collect)]
+#[collect(require_static)]
+pub struct DisplayProperty {
+    get: DisplayGetter,
+    set: Option<DisplaySetter>,
 }
 
-pub type DisplayGetter<'gc> = fn(&mut Activation<'_, 'gc, '_>, DisplayObject<'gc>) -> Value<'gc>;
+pub type DisplayGetter =
+    for<'gc> fn(&mut Activation<'_, 'gc, '_>, DisplayObject<'gc>) -> Value<'gc>;
+pub type DisplaySetter = for<'gc> fn(
+    &mut Activation<'_, 'gc, '_>,
+    DisplayObject<'gc>,
+    Value<'gc>,
+) -> Result<(), Error<'gc>>;
 
-pub type DisplaySetter<'gc> =
-    fn(&mut Activation<'_, 'gc, '_>, DisplayObject<'gc>, Value<'gc>) -> Result<(), Error<'gc>>;
-
-impl<'gc> DisplayProperty<'gc> {
+impl<'gc> DisplayProperty {
     pub fn get(
         &self,
         activation: &mut Activation<'_, 'gc, '_>,
@@ -378,16 +382,10 @@ impl<'gc> DisplayProperty<'gc> {
     }
 }
 
-unsafe impl<'gc> Collect for DisplayProperty<'gc> {
-    fn needs_trace() -> bool {
-        false
-    }
-}
-
 /// The map from key/index to function pointers for special display object properties.
 #[derive(Collect)]
 #[collect(no_drop)]
-pub struct DisplayPropertyMap<'gc>(PropertyMap<'gc, DisplayProperty<'gc>>);
+pub struct DisplayPropertyMap<'gc>(PropertyMap<'gc, DisplayProperty>);
 
 impl<'gc> DisplayPropertyMap<'gc> {
     /// Creates the display property map.
@@ -428,7 +426,7 @@ impl<'gc> DisplayPropertyMap<'gc> {
 
     /// Gets a property slot by name.
     /// Used by `GetMember`, `GetVariable`, `SetMember`, and `SetVariable`.
-    pub fn get_by_name(&self, name: AvmString<'gc>) -> Option<&DisplayProperty<'gc>> {
+    pub fn get_by_name(&self, name: AvmString<'gc>) -> Option<&DisplayProperty> {
         // Display object properties are case insensitive, regardless of SWF version!?
         // TODO: Another string alloc; optimize this eventually.
         self.0.get(name, false)
@@ -438,15 +436,15 @@ impl<'gc> DisplayPropertyMap<'gc> {
     /// The order is defined by the SWF specs.
     /// Used by `GetProperty`/`SetProperty`.
     /// SWF19 pp. 85-86
-    pub fn get_by_index(&self, index: usize) -> Option<&DisplayProperty<'gc>> {
+    pub fn get_by_index(&self, index: usize) -> Option<&DisplayProperty> {
         self.0.get_index(index)
     }
 
     fn add_property(
         &mut self,
         name: AvmString<'gc>,
-        get: DisplayGetter<'gc>,
-        set: Option<DisplaySetter<'gc>>,
+        get: DisplayGetter,
+        set: Option<DisplaySetter>,
     ) {
         let prop = DisplayProperty { get, set };
         self.0.insert(name, prop, false);

core/src/avm2/method.rs

@@ -7,7 +7,7 @@ use crate::avm2::value::{abc_default_value, Value};
 use crate::avm2::Error;
 use crate::avm2::Multiname;
 use crate::string::AvmString;
-use gc_arena::{Collect, CollectionContext, Gc, MutationContext};
+use gc_arena::{Collect, Gc, MutationContext};
 use std::fmt;
 use std::ops::Deref;
 use std::rc::Rc;
@@ -256,9 +256,11 @@ impl<'gc> BytecodeMethod<'gc> {
 }
 
 /// An uninstantiated method
-#[derive(Clone)]
+#[derive(Clone, Collect)]
+#[collect(no_drop)]
 pub struct NativeMethod<'gc> {
     /// The function to call to execute the method.
+    #[collect(require_static)]
     pub method: NativeMethodImpl,
 
     /// The name of the method.
@@ -272,12 +274,6 @@ pub struct NativeMethod<'gc> {
     pub is_variadic: bool,
 }
 
-unsafe impl<'gc> Collect for NativeMethod<'gc> {
-    fn trace(&self, cc: CollectionContext) {
-        self.signature.trace(cc);
-    }
-}
-
 impl<'gc> fmt::Debug for NativeMethod<'gc> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("NativeMethod")