1 files changed, 15 insertions, 9 deletions

diff --git a/components/layout_2020/layout_debug.rs b/components/layout_2020/layout_debug.rs
index 642e6b8a538..da3c1886971 100644
--- a/components/layout_2020/layout_debug.rs
+++ b/components/layout_2020/layout_debug.rs
@@ -48,7 +48,7 @@ struct ScopeData {
     name: String,
     pre: TreeValues,
     post: TreeValues,
-    children: Vec<Box<ScopeData>>,
+    children: Vec<ScopeData>,
 }
 
 impl ScopeData {
@@ -71,19 +71,19 @@ impl ScopeData {
 struct State {
     fragment_tree: Arc<FragmentTree>,
     box_tree: Arc<BoxTree>,
-    scope_stack: Vec<Box<ScopeData>>,
+    scope_stack: Vec<ScopeData>,
 }
 
 /// A layout debugging scope. The entire state of the box and fragment trees
 /// will be output at the beginning and end of this scope.
 impl Scope {
     pub fn new(name: String) -> Scope {
-        STATE_KEY.with(|ref r| {
+        STATE_KEY.with(|r| {
             if let Some(ref mut state) = *r.borrow_mut() {
                 let box_tree = to_value(&state.box_tree).unwrap();
                 let fragment_tree = to_value(&state.fragment_tree).unwrap();
                 let data = Box::new(ScopeData::new(name.clone(), box_tree, fragment_tree));
-                state.scope_stack.push(data);
+                state.scope_stack.push(*data);
             }
         });
         Scope
@@ -93,7 +93,7 @@ impl Scope {
 #[cfg(debug_assertions)]
 impl Drop for Scope {
     fn drop(&mut self) {
-        STATE_KEY.with(|ref r| {
+        STATE_KEY.with(|r| {
             if let Some(ref mut state) = *r.borrow_mut() {
                 let mut current_scope = state.scope_stack.pop().unwrap();
                 current_scope.post = TreeValues {
@@ -110,13 +110,13 @@ impl Drop for Scope {
 /// Begin a layout debug trace. If this has not been called,
 /// creating debug scopes has no effect.
 pub fn begin_trace(box_tree: Arc<BoxTree>, fragment_tree: Arc<FragmentTree>) {
-    assert!(STATE_KEY.with(|ref r| r.borrow().is_none()));
+    assert!(STATE_KEY.with(|r| r.borrow().is_none()));
 
-    STATE_KEY.with(|ref r| {
+    STATE_KEY.with(|r| {
         let box_tree_value = to_value(&box_tree).unwrap();
         let fragment_tree_value = to_value(&fragment_tree).unwrap();
         let state = State {
-            scope_stack: vec![Box::new(ScopeData::new(
+            scope_stack: vec![*Box::new(ScopeData::new(
                 "root".to_owned(),
                 box_tree_value,
                 fragment_tree_value,
@@ -132,7 +132,7 @@ pub fn begin_trace(box_tree: Arc<BoxTree>, fragment_tree: Arc<FragmentTree>) {
 /// trace to disk in the current directory. The output
 /// file can then be viewed with an external tool.
 pub fn end_trace(generation: u32) {
-    let mut thread_state = STATE_KEY.with(|ref r| r.borrow_mut().take().unwrap());
+    let mut thread_state = STATE_KEY.with(|r| r.borrow_mut().take().unwrap());
     assert_eq!(thread_state.scope_stack.len(), 1);
     let mut root_scope = thread_state.scope_stack.pop().unwrap();
     root_scope.post = TreeValues {
@@ -170,6 +170,12 @@ impl DebugId {
     }
 }
 
+impl Default for DebugId {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 #[cfg(not(debug_assertions))]
 impl Serialize for DebugId {
     fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {