clippy: Fix needless_borrow warnings in components/script (#31928)

components/script/canvas_state.rs

@@ -584,7 +584,7 @@ impl CanvasState {
     }
 
     pub fn mark_as_dirty(&self, canvas: Option<&HTMLCanvasElement>) {
-        if let Some(ref canvas) = canvas {
+        if let Some(canvas) = canvas {
             canvas.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
         }
     }
@@ -1705,7 +1705,7 @@ pub fn parse_color(canvas: Option<&HTMLCanvasElement>, string: &str) -> Result<R
                 // Whenever "currentColor" is used as a color in the PaintRenderingContext2D API,
                 // it is treated as opaque black.
                 None => AbsoluteColor::BLACK,
-                Some(ref canvas) => {
+                Some(canvas) => {
                     let canvas_element = canvas.upcast::<Element>();
                     match canvas_element.style() {
                         Some(ref s) if canvas_element.has_css_layout_box() => {

components/script/dom/bluetoothpermissionresult.rs

@@ -102,10 +102,10 @@ impl AsyncBluetoothListener for BluetoothPermissionResult {
                 self.set_state(PermissionState::Granted);
                 let bluetooth = self.get_bluetooth();
                 let mut device_instance_map = bluetooth.get_device_map().borrow_mut();
-                if let Some(ref existing_device) = device_instance_map.get(&device.id) {
+                if let Some(existing_device) = device_instance_map.get(&device.id) {
                     // https://webbluetoothcg.github.io/web-bluetooth/#request-the-bluetooth-permission
                     // Step 3.
-                    self.set_devices(vec![Dom::from_ref(*existing_device)]);
+                    self.set_devices(vec![Dom::from_ref(existing_device)]);
 
                     // https://w3c.github.io/permissions/#dom-permissions-request
                     // Step 8.

components/script/dom/document.rs

@@ -3529,7 +3529,7 @@ impl Document {
         self.id_map
             .borrow()
             .get(id)
-            .map(|ref elements| DomRoot::from_ref(&*(*elements)[0]))
+            .map(|elements| DomRoot::from_ref(&*elements[0]))
     }
 
     pub fn ensure_pending_restyle(&self, el: &Element) -> RefMut<PendingRestyle> {

components/script/dom/documentfragment.rs

@@ -82,7 +82,7 @@ impl DocumentFragmentMethods for DocumentFragment {
         self.id_map
             .borrow()
             .get(&id)
-            .map(|ref elements| DomRoot::from_ref(&*(*elements)[0]))
+            .map(|elements| DomRoot::from_ref(&*elements[0]))
     }
 
     // https://dom.spec.whatwg.org/#dom-parentnode-firstelementchild

components/script/dom/element.rs

@@ -3246,7 +3246,7 @@ impl<'a> SelectorsElement for DomRoot<Element> {
         operation: &AttrSelectorOperation<&AtomString>,
     ) -> bool {
         match *ns {
-            NamespaceConstraint::Specific(ref ns) => self
+            NamespaceConstraint::Specific(ns) => self
                 .get_attribute(ns, local_name)
                 .map_or(false, |attr| attr.value().eval_selector(operation)),
             NamespaceConstraint::Any => self.attrs.borrow().iter().any(|attr| {

components/script/dom/globalscope.rs

@@ -1209,7 +1209,7 @@ impl GlobalScope {
             if let Some(channels) = channels.get(&channel_name) {
                 channels
                     .iter()
-                    .filter(|ref channel| {
+                    .filter(|channel| {
                         // Step 8.
                         // Filter out the sender.
                         if let Some(id) = channel_id {
@@ -1355,7 +1355,7 @@ impl GlobalScope {
         {
             let to_be_removed: Vec<MessagePortId> = message_ports
                 .iter()
-                .filter_map(|(id, ref managed_port)| {
+                .filter_map(|(id, managed_port)| {
                     if managed_port.closed {
                         // Let the constellation know to drop this port and the one it is entangled with,
                         // and to forward this message to the script-process where the entangled is found.
@@ -1388,7 +1388,7 @@ impl GlobalScope {
             &mut *self.broadcast_channel_state.borrow_mut()
         {
             channels.retain(|name, ref mut channels| {
-                channels.retain(|ref chan| !chan.closed());
+                channels.retain(|chan| !chan.closed());
                 if channels.is_empty() {
                     let _ = self.script_to_constellation_chan().send(
                         ScriptMsg::RemoveBroadcastChannelNameInRouter(

components/script/dom/htmlinputelement.rs

@@ -2483,7 +2483,7 @@ impl VirtualMethods for HTMLInputElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
         self.upcast::<Element>()
@@ -2620,7 +2620,7 @@ impl VirtualMethods for HTMLInputElement {
         maybe_doc: Option<&Document>,
         clone_children: CloneChildrenFlag,
     ) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.cloning_steps(copy, maybe_doc, clone_children);
         }
         let elem = copy.downcast::<HTMLInputElement>().unwrap();

components/script/dom/htmllegendelement.rs

@@ -59,7 +59,7 @@ impl VirtualMethods for HTMLLegendElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
 

components/script/dom/htmllinkelement.rs

@@ -239,7 +239,7 @@ impl VirtualMethods for HTMLLinkElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
 
@@ -263,7 +263,7 @@ impl VirtualMethods for HTMLLinkElement {
     }
 
     fn unbind_from_tree(&self, context: &UnbindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.unbind_from_tree(context);
         }
 

components/script/dom/htmlmetaelement.rs

@@ -227,7 +227,7 @@ impl VirtualMethods for HTMLMetaElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
 
@@ -245,7 +245,7 @@ impl VirtualMethods for HTMLMetaElement {
     }
 
     fn unbind_from_tree(&self, context: &UnbindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.unbind_from_tree(context);
         }
 

components/script/dom/htmloptgroupelement.rs

@@ -123,7 +123,7 @@ impl VirtualMethods for HTMLOptGroupElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
 

components/script/dom/htmloptionelement.rs

@@ -336,7 +336,7 @@ impl VirtualMethods for HTMLOptionElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
 

components/script/dom/htmlscriptelement.rs

@@ -1254,7 +1254,7 @@ impl VirtualMethods for HTMLScriptElement {
     }
 
     fn children_changed(&self, mutation: &ChildrenMutation) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.children_changed(mutation);
         }
         if !self.parser_inserted.get() && self.upcast::<Node>().is_connected() {
@@ -1263,7 +1263,7 @@ impl VirtualMethods for HTMLScriptElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
 
@@ -1281,7 +1281,7 @@ impl VirtualMethods for HTMLScriptElement {
         maybe_doc: Option<&Document>,
         clone_children: CloneChildrenFlag,
     ) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.cloning_steps(copy, maybe_doc, clone_children);
         }
 

components/script/dom/htmlselectelement.rs

@@ -447,7 +447,7 @@ impl VirtualMethods for HTMLSelectElement {
     }
 
     fn bind_to_tree(&self, context: &BindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.bind_to_tree(context);
         }
 

components/script/dom/htmlstyleelement.rs

@@ -225,7 +225,7 @@ impl VirtualMethods for HTMLStyleElement {
     }
 
     fn unbind_from_tree(&self, context: &UnbindContext) {
-        if let Some(ref s) = self.super_type() {
+        if let Some(s) = self.super_type() {
             s.unbind_from_tree(context);
         }
 

components/script/dom/htmltableelement.rs

@@ -50,7 +50,7 @@ impl CollectionFilter for TableRowFilter {
             (root.is_parent_of(elem.upcast()) ||
                 self.sections
                     .iter()
-                    .any(|ref section| section.is_parent_of(elem.upcast())))
+                    .any(|section| section.is_parent_of(elem.upcast())))
     }
 }
 

components/script/dom/node.rs

@@ -232,12 +232,12 @@ impl Node {
         assert!(new_child.prev_sibling.get().is_none());
         assert!(new_child.next_sibling.get().is_none());
         match before {
-            Some(ref before) => {
+            Some(before) => {
                 assert!(before.parent_node.get().as_deref() == Some(self));
                 let prev_sibling = before.GetPreviousSibling();
                 match prev_sibling {
                     None => {
-                        assert!(self.first_child.get().as_deref() == Some(*before));
+                        assert!(self.first_child.get().as_deref() == Some(before));
                         self.first_child.set(Some(new_child));
                     },
                     Some(ref prev_sibling) => {

components/script/dom/rtcpeerconnection.rs

@@ -206,7 +206,7 @@ impl RTCPeerConnection {
         let signaller = this.make_signaller();
         *this.controller.borrow_mut() = Some(ServoMedia::get().unwrap().create_webrtc(signaller));
         if let Some(ref servers) = config.iceServers {
-            if let Some(ref server) = servers.get(0) {
+            if let Some(server) = servers.get(0) {
                 let server = match server.urls {
                     StringOrStringSequence::String(ref s) => Some(s.clone()),
                     StringOrStringSequence::StringSequence(ref s) => s.get(0).cloned(),

components/script/layout_dom/element.rs

@@ -255,8 +255,8 @@ impl<'dom, LayoutDataType: LayoutDataTrait> style::dom::TElement
     where
         F: FnMut(&AtomIdent),
     {
-        if let Some(ref classes) = self.element.get_classes_for_layout() {
+        if let Some(classes) = self.element.get_classes_for_layout() {
-            for class in *classes {
+            for class in classes {
                 callback(AtomIdent::cast(class))
             }
         }
@@ -520,7 +520,7 @@ impl<'dom, LayoutDataType: LayoutDataTrait> ::selectors::Element
         operation: &AttrSelectorOperation<&AtomString>,
     ) -> bool {
         match *ns {
-            NamespaceConstraint::Specific(ref ns) => self
+            NamespaceConstraint::Specific(ns) => self
                 .get_attr_enum(ns, local_name)
                 .map_or(false, |value| value.eval_selector(operation)),
             NamespaceConstraint::Any => self
@@ -875,7 +875,7 @@ impl<'dom, LayoutDataType: LayoutDataTrait> ::selectors::Element
         operation: &AttrSelectorOperation<&AtomString>,
     ) -> bool {
         match *ns {
-            NamespaceConstraint::Specific(ref ns) => self
+            NamespaceConstraint::Specific(ns) => self
                 .get_attr_enum(ns, local_name)
                 .map_or(false, |value| value.eval_selector(operation)),
             NamespaceConstraint::Any => self