core: load_device_font register function must be &mut

core/src/backend/ui.rs

@@ -96,7 +96,7 @@ pub trait UiBackend: Downcast {
         name: &str,
         is_bold: bool,
         is_italic: bool,
-        register: &dyn FnMut(FontDefinition),
+        register: &mut dyn FnMut(FontDefinition),
     );
 
     /// Displays a file selection dialog, returning None if the dialog cannot be displayed
@@ -278,7 +278,7 @@ impl UiBackend for NullUiBackend {
         _name: &str,
         _is_bold: bool,
         _is_italic: bool,
-        _register: &dyn FnMut(FontDefinition),
+        _register: &mut dyn FnMut(FontDefinition),
     ) {
     }
 

core/src/library.rs

@@ -490,7 +490,7 @@ impl<'gc> Library<'gc> {
             .insert((name.to_string(), is_bold, is_italic));
         if new_request {
             // First time asking for this font, see if our backend can provide anything relevant
-            ui.load_device_font(name, is_bold, is_italic, &|definition| {
+            ui.load_device_font(name, is_bold, is_italic, &mut |definition| {
                 self.register_device_font(gc_context, renderer, definition)
             });
         }

desktop/src/backends/ui.rs

@@ -252,7 +252,7 @@ impl UiBackend for DesktopUiBackend {
         _name: &str,
         _is_bold: bool,
         _is_italic: bool,
-        _register: &dyn FnMut(FontDefinition),
+        _register: &mut dyn FnMut(FontDefinition),
     ) {
     }
 

tests/framework/src/backends/ui.rs

@@ -115,7 +115,7 @@ impl UiBackend for TestUiBackend {
         _name: &str,
         _is_bold: bool,
         _is_italic: bool,
-        _register: &dyn FnMut(FontDefinition),
+        _register: &mut dyn FnMut(FontDefinition),
     ) {
     }
 

web/src/ui.rs

@@ -265,7 +265,7 @@ impl UiBackend for WebUiBackend {
         _name: &str,
         _is_bold: bool,
         _is_italic: bool,
-        _register: &dyn FnMut(FontDefinition),
+        _register: &mut dyn FnMut(FontDefinition),
     ) {
         // Because fonts must be loaded instantly (no async),
         // we actually just provide them all upfront at time of Player creation.