Auto merge of #24644 - saschanaz:sequence-default, r=jdm

Use IDL sequence default value

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---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #24643

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- [x] There are tests for these changes

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13 files changed, 40 insertions, 65 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 86ee03d7ddd..77c3c776c3e 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -6388,8 +6388,11 @@ class CGDictionary(CGThing):
     def struct(self):
         d = self.dictionary
         if d.parent:
-            inheritance = "    pub parent: %s::%s,\n" % (self.makeModuleName(d.parent),
-                                                         self.makeClassName(d.parent))
+            typeName = "%s::%s" % (self.makeModuleName(d.parent),
+                                   self.makeClassName(d.parent))
+            if type_needs_tracing(d.parent):
+                typeName = "RootedTraceableBox<%s>" % typeName
+            inheritance = "    pub parent: %s,\n" % typeName
         else:
             inheritance = ""
         memberDecls = ["    pub %s: %s," %
@@ -6520,10 +6523,7 @@ class CGDictionary(CGThing):
             })
 
     def membersNeedTracing(self):
-        for member, _ in self.memberInfo:
-            if type_needs_tracing(member.type):
-                return True
-        return False
+        return type_needs_tracing(self.dictionary)
 
     @staticmethod
     def makeDictionaryName(dictionary):
diff --git a/components/script/dom/bluetooth.rs b/components/script/dom/bluetooth.rs
index 989bcce27b7..fad367bb454 100644
--- a/components/script/dom/bluetooth.rs
+++ b/components/script/dom/bluetooth.rs
@@ -164,7 +164,7 @@ impl Bluetooth {
         &self,
         p: &Rc<Promise>,
         filters: &Option<Vec<BluetoothLEScanFilterInit>>,
-        optional_services: &Option<Vec<BluetoothServiceUUID>>,
+        optional_services: &[BluetoothServiceUUID],
         sender: IpcSender<BluetoothResponseResult>,
     ) {
         // TODO: Step 1: Triggered by user activation.
@@ -197,23 +197,21 @@ impl Bluetooth {
         }
 
         let mut optional_services_uuids = vec![];
-        if let &Some(ref opt_services) = optional_services {
-            for opt_service in opt_services {
-                // Step 2.5 - 2.6.
-                let uuid = match BluetoothUUID::service(opt_service.clone()) {
-                    Ok(u) => u.to_string(),
-                    Err(e) => {
-                        p.reject_error(e);
-                        return;
-                    },
-                };
+        for opt_service in optional_services {
+            // Step 2.5 - 2.6.
+            let uuid = match BluetoothUUID::service(opt_service.clone()) {
+                Ok(u) => u.to_string(),
+                Err(e) => {
+                    p.reject_error(e);
+                    return;
+                },
+            };
 
-                // Step 2.7.
-                // Note: What we are doing here, is adding the not blocklisted UUIDs to the result vector,
-                // instead of removing them from an already filled vector.
-                if !uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
-                    optional_services_uuids.push(uuid);
-                }
+            // Step 2.7.
+            // Note: What we are doing here, is adding the not blocklisted UUIDs to the result vector,
+            // instead of removing them from an already filled vector.
+            if !uuid_is_blocklisted(uuid.as_ref(), Blocklist::All) {
+                optional_services_uuids.push(uuid);
             }
         }
 
diff --git a/components/script/dom/dedicatedworkerglobalscope.rs b/components/script/dom/dedicatedworkerglobalscope.rs
index 3745ef9f1ac..f5895379003 100644
--- a/components/script/dom/dedicatedworkerglobalscope.rs
+++ b/components/script/dom/dedicatedworkerglobalscope.rs
@@ -619,8 +619,6 @@ impl DedicatedWorkerGlobalScopeMethods for DedicatedWorkerGlobalScope {
         let mut rooted = CustomAutoRooter::new(
             options
                 .transfer
-                .as_ref()
-                .unwrap_or(&Vec::with_capacity(0))
                 .iter()
                 .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
                 .collect(),
diff --git a/components/script/dom/dissimilaroriginwindow.rs b/components/script/dom/dissimilaroriginwindow.rs
index c628923604e..ac596048717 100644
--- a/components/script/dom/dissimilaroriginwindow.rs
+++ b/components/script/dom/dissimilaroriginwindow.rs
@@ -141,15 +141,9 @@ impl DissimilarOriginWindowMethods for DissimilarOriginWindow {
         cx: JSContext,
         message: HandleValue,
         target_origin: USVString,
-        mut transfer: CustomAutoRooterGuard<Option<Vec<*mut JSObject>>>,
+        transfer: CustomAutoRooterGuard<Vec<*mut JSObject>>,
     ) -> ErrorResult {
-        if transfer.is_some() {
-            let mut rooted = CustomAutoRooter::new(transfer.take().unwrap());
-            let transfer = Some(CustomAutoRooterGuard::new(*cx, &mut rooted));
-            self.post_message_impl(&target_origin, cx, message, transfer)
-        } else {
-            self.post_message_impl(&target_origin, cx, message, None)
-        }
+        self.post_message_impl(&target_origin, cx, message, transfer)
     }
 
     /// https://html.spec.whatwg.org/multipage/#dom-window-postmessage-options
@@ -161,14 +155,13 @@ impl DissimilarOriginWindowMethods for DissimilarOriginWindow {
     ) -> ErrorResult {
         let mut rooted = CustomAutoRooter::new(
             options
+                .parent
                 .transfer
-                .as_ref()
-                .unwrap_or(&Vec::with_capacity(0))
                 .iter()
                 .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
                 .collect(),
         );
-        let transfer = Some(CustomAutoRooterGuard::new(*cx, &mut rooted));
+        let transfer = CustomAutoRooterGuard::new(*cx, &mut rooted);
 
         self.post_message_impl(&options.targetOrigin, cx, message, transfer)
     }
@@ -208,10 +201,10 @@ impl DissimilarOriginWindow {
         target_origin: &USVString,
         cx: JSContext,
         message: HandleValue,
-        transfer: Option<CustomAutoRooterGuard<Vec<*mut JSObject>>>,
+        transfer: CustomAutoRooterGuard<Vec<*mut JSObject>>,
     ) -> ErrorResult {
         // Step 6-7.
-        let data = structuredclone::write(cx, message, transfer)?;
+        let data = structuredclone::write(cx, message, Some(transfer))?;
 
         self.post_message(target_origin, data)
     }
diff --git a/components/script/dom/messageport.rs b/components/script/dom/messageport.rs
index 67d470a10a2..3198df50923 100644
--- a/components/script/dom/messageport.rs
+++ b/components/script/dom/messageport.rs
@@ -294,8 +294,6 @@ impl MessagePortMethods for MessagePort {
         let mut rooted = CustomAutoRooter::new(
             options
                 .transfer
-                .as_ref()
-                .unwrap_or(&Vec::with_capacity(0))
                 .iter()
                 .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
                 .collect(),
diff --git a/components/script/dom/serviceworker.rs b/components/script/dom/serviceworker.rs
index ec64036d305..43e7245f3c5 100644
--- a/components/script/dom/serviceworker.rs
+++ b/components/script/dom/serviceworker.rs
@@ -141,8 +141,6 @@ impl ServiceWorkerMethods for ServiceWorker {
         let mut rooted = CustomAutoRooter::new(
             options
                 .transfer
-                .as_ref()
-                .unwrap_or(&Vec::with_capacity(0))
                 .iter()
                 .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
                 .collect(),
diff --git a/components/script/dom/webidls/Bluetooth.webidl b/components/script/dom/webidls/Bluetooth.webidl
index a24206036bf..e5e135c0577 100644
--- a/components/script/dom/webidls/Bluetooth.webidl
+++ b/components/script/dom/webidls/Bluetooth.webidl
@@ -21,7 +21,7 @@ dictionary BluetoothLEScanFilterInit {
 
 dictionary RequestDeviceOptions {
   sequence<BluetoothLEScanFilterInit> filters;
-  sequence<BluetoothServiceUUID> optionalServices /*= []*/;
+  sequence<BluetoothServiceUUID> optionalServices = [];
   boolean acceptAllDevices = false;
 };
 
diff --git a/components/script/dom/webidls/BluetoothPermissionResult.webidl b/components/script/dom/webidls/BluetoothPermissionResult.webidl
index 4f9f2871a2e..95c06797aef 100644
--- a/components/script/dom/webidls/BluetoothPermissionResult.webidl
+++ b/components/script/dom/webidls/BluetoothPermissionResult.webidl
@@ -8,7 +8,7 @@ dictionary BluetoothPermissionDescriptor : PermissionDescriptor {
   DOMString deviceId;
   // These match RequestDeviceOptions.
   sequence<BluetoothLEScanFilterInit> filters;
-  sequence<BluetoothServiceUUID> optionalServices/* = []*/;
+  sequence<BluetoothServiceUUID> optionalServices = [];
   boolean acceptAllDevices = false;
 };
 
diff --git a/components/script/dom/webidls/DissimilarOriginWindow.webidl b/components/script/dom/webidls/DissimilarOriginWindow.webidl
index bbfcb75b69b..b690736469a 100644
--- a/components/script/dom/webidls/DissimilarOriginWindow.webidl
+++ b/components/script/dom/webidls/DissimilarOriginWindow.webidl
@@ -25,7 +25,7 @@ interface DissimilarOriginWindow : GlobalScope {
 
   void close();
   readonly attribute boolean closed;
-  [Throws] void postMessage(any message, USVString targetOrigin, optional sequence<object> transfer /*= []*/);
+  [Throws] void postMessage(any message, USVString targetOrigin, optional sequence<object> transfer = []);
   [Throws] void postMessage(any message, optional WindowPostMessageOptions options = {});
   attribute any opener;
   void blur();
diff --git a/components/script/dom/webidls/MessagePort.webidl b/components/script/dom/webidls/MessagePort.webidl
index c2fd1dbd1f4..58a3f06a960 100644
--- a/components/script/dom/webidls/MessagePort.webidl
+++ b/components/script/dom/webidls/MessagePort.webidl
@@ -8,7 +8,7 @@
 
 [Exposed=(Window,Worker)]
 interface MessagePort : EventTarget {
-  [Throws] void postMessage(any message, sequence<object> transfer /*= []*/);
+  [Throws] void postMessage(any message, sequence<object> transfer);
   [Throws] void postMessage(any message, optional PostMessageOptions options = {});
   void start();
   void close();
@@ -19,5 +19,5 @@ interface MessagePort : EventTarget {
 };
 
 dictionary PostMessageOptions {
-  sequence<object> transfer;
+  sequence<object> transfer = [];
 };
diff --git a/components/script/dom/webidls/Window.webidl b/components/script/dom/webidls/Window.webidl
index 26edbca5c7a..f2cdeeb18a5 100644
--- a/components/script/dom/webidls/Window.webidl
+++ b/components/script/dom/webidls/Window.webidl
@@ -64,7 +64,7 @@
   void cancelAnimationFrame(unsigned long handle);
 
   [Throws]
-  void postMessage(any message, USVString targetOrigin, optional sequence<object> transfer /*= []*/);
+  void postMessage(any message, USVString targetOrigin, optional sequence<object> transfer = []);
   [Throws]
   void postMessage(any message, optional WindowPostMessageOptions options = {});
 
@@ -175,7 +175,6 @@ partial interface Window {
    readonly attribute unsigned long runningAnimationCount;
 };
 
-dictionary WindowPostMessageOptions {
+dictionary WindowPostMessageOptions : PostMessageOptions {
    USVString targetOrigin = "/";
-   sequence<object> transfer;
 };
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 37b5b5e3b2c..70099ee5866 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -979,19 +979,13 @@ impl WindowMethods for Window {
         cx: JSContext,
         message: HandleValue,
         target_origin: USVString,
-        mut transfer: CustomAutoRooterGuard<Option<Vec<*mut JSObject>>>,
+        transfer: CustomAutoRooterGuard<Vec<*mut JSObject>>,
     ) -> ErrorResult {
         let incumbent = GlobalScope::incumbent().expect("no incumbent global?");
         let source = incumbent.as_window();
         let source_origin = source.Document().origin().immutable().clone();
 
-        if transfer.is_some() {
-            let mut rooted = CustomAutoRooter::new(transfer.take().unwrap());
-            let transfer = Some(CustomAutoRooterGuard::new(*cx, &mut rooted));
-            self.post_message_impl(&target_origin, source_origin, source, cx, message, transfer)
-        } else {
-            self.post_message_impl(&target_origin, source_origin, source, cx, message, None)
-        }
+        self.post_message_impl(&target_origin, source_origin, source, cx, message, transfer)
     }
 
     /// <https://html.spec.whatwg.org/multipage/#dom-messageport-postmessage>
@@ -1003,14 +997,13 @@ impl WindowMethods for Window {
     ) -> ErrorResult {
         let mut rooted = CustomAutoRooter::new(
             options
+                .parent
                 .transfer
-                .as_ref()
-                .unwrap_or(&Vec::with_capacity(0))
                 .iter()
                 .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
                 .collect(),
         );
-        let transfer = Some(CustomAutoRooterGuard::new(*cx, &mut rooted));
+        let transfer = CustomAutoRooterGuard::new(*cx, &mut rooted);
 
         let incumbent = GlobalScope::incumbent().expect("no incumbent global?");
         let source = incumbent.as_window();
@@ -1330,10 +1323,10 @@ impl Window {
         source: &Window,
         cx: JSContext,
         message: HandleValue,
-        transfer: Option<CustomAutoRooterGuard<Vec<*mut JSObject>>>,
+        transfer: CustomAutoRooterGuard<Vec<*mut JSObject>>,
     ) -> ErrorResult {
         // Step 1-2, 6-8.
-        let data = structuredclone::write(cx, message, transfer)?;
+        let data = structuredclone::write(cx, message, Some(transfer))?;
 
         // Step 3-5.
         let target_origin = match target_origin.0[..].as_ref() {
diff --git a/components/script/dom/worker.rs b/components/script/dom/worker.rs
index 3b9830f8ded..f08bdcab79e 100644
--- a/components/script/dom/worker.rs
+++ b/components/script/dom/worker.rs
@@ -218,8 +218,6 @@ impl WorkerMethods for Worker {
         let mut rooted = CustomAutoRooter::new(
             options
                 .transfer
-                .as_ref()
-                .unwrap_or(&Vec::with_capacity(0))
                 .iter()
                 .map(|js: &RootedTraceableBox<Heap<*mut JSObject>>| js.get())
                 .collect(),