Auto merge of #24377 - saschanaz:record-support, r=nox

Support WebIDL `record<>`

<!-- Please describe your changes on the following line: -->

Rebased @taki-zaro's work (#20318).

---
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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 #15012 and closes #20318. Possibly also closes #21463.

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- [x] There are tests for these changes

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12 files changed, 318 insertions, 251 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 103450f78f3..01b7fc698ba 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -77,14 +77,13 @@ def innerContainerType(type):
 
 def wrapInNativeContainerType(type, inner):
     if type.isSequence():
-        containerType = "Vec"
+        return CGWrapper(inner, pre="Vec<", post=">")
     elif type.isRecord():
-        containerType = "MozMap"
+        key = type.inner.keyType if type.nullable() else type.keyType
+        return CGRecord(key, inner)
     else:
         raise TypeError("Unexpected container type %s", type)
 
-    return CGWrapper(inner, pre=containerType + "<", post=">")
-
 
 builtinNames = {
     IDLType.Tags.bool: 'bool',
@@ -1905,6 +1904,30 @@ class CGWrapper(CGThing):
         return self.pre + defn + self.post
 
 
+class CGRecord(CGThing):
+    """
+    CGThing that wraps value CGThing in record with key type equal to keyType parameter
+    """
+    def __init__(self, keyType, value):
+        CGThing.__init__(self)
+        assert keyType.isString()
+        self.keyType = keyType
+        self.value = value
+
+    def define(self):
+        if self.keyType.isByteString():
+            keyDef = "ByteString"
+        elif self.keyType.isDOMString():
+            keyDef = "DOMString"
+        elif self.keyType.isUSVString():
+            keyDef = "USVString"
+        else:
+            assert False
+
+        defn = keyDef + ", " + self.value.define()
+        return "Record<" + defn + ">"
+
+
 class CGImports(CGWrapper):
     """
     Generates the appropriate import/use statements.
@@ -2024,7 +2047,7 @@ class CGImports(CGWrapper):
                     extras += [descriptor.path, descriptor.bindingPath]
                     parentName = descriptor.getParentName()
             elif t.isType() and t.isRecord():
-                extras += ['crate::dom::bindings::mozmap::MozMap']
+                extras += ['crate::dom::bindings::record::Record']
             elif isinstance(t, IDLPromiseType):
                 extras += ['crate::dom::promise::Promise']
             else:
@@ -2373,7 +2396,7 @@ def UnionTypes(descriptors, dictionaries, callbacks, typedefs, config):
         'crate::dom::bindings::conversions::StringificationBehavior',
         'crate::dom::bindings::conversions::root_from_handlevalue',
         'std::ptr::NonNull',
-        'crate::dom::bindings::mozmap::MozMap',
+        'crate::dom::bindings::record::Record',
         'crate::dom::bindings::num::Finite',
         'crate::dom::bindings::root::DomRoot',
         'crate::dom::bindings::str::ByteString',
@@ -6054,7 +6077,7 @@ def generate_imports(config, cgthings, descriptors, callbacks=None, dictionaries
         'crate::dom::bindings::proxyhandler::ensure_expando_object',
         'crate::dom::bindings::proxyhandler::fill_property_descriptor',
         'crate::dom::bindings::proxyhandler::get_expando_object',
-        'crate::dom::bindings::mozmap::MozMap',
+        'crate::dom::bindings::record::Record',
         'std::ptr::NonNull',
         'crate::dom::bindings::num::Finite',
         'crate::dom::bindings::str::ByteString',
diff --git a/components/script/dom/bindings/mod.rs b/components/script/dom/bindings/mod.rs
index c6759edb360..48ee7674c92 100644
--- a/components/script/dom/bindings/mod.rs
+++ b/components/script/dom/bindings/mod.rs
@@ -143,10 +143,10 @@ pub mod htmlconstructor;
 pub mod inheritance;
 pub mod interface;
 pub mod iterable;
-pub mod mozmap;
 pub mod namespace;
 pub mod num;
 pub mod proxyhandler;
+pub mod record;
 pub mod refcounted;
 pub mod reflector;
 pub mod root;
diff --git a/components/script/dom/bindings/mozmap.rs b/components/script/dom/bindings/mozmap.rs
deleted file mode 100644
index f5961e5bdda..00000000000
--- a/components/script/dom/bindings/mozmap.rs
+++ /dev/null
@@ -1,135 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
-
-//! The `MozMap` (open-ended dictionary) type.
-
-use crate::dom::bindings::conversions::jsid_to_string;
-use crate::dom::bindings::error::report_pending_exception;
-use crate::dom::bindings::str::DOMString;
-use indexmap::IndexMap;
-use js::conversions::{ConversionResult, FromJSValConvertible, ToJSValConvertible};
-use js::jsapi::JSContext;
-use js::jsapi::JS_NewPlainObject;
-use js::jsapi::JSITER_HIDDEN;
-use js::jsapi::JSITER_OWNONLY;
-use js::jsapi::JSITER_SYMBOLS;
-use js::jsapi::JSPROP_ENUMERATE;
-use js::jsval::ObjectValue;
-use js::jsval::UndefinedValue;
-use js::rust::wrappers::GetPropertyKeys;
-use js::rust::wrappers::JS_DefineUCProperty2;
-use js::rust::wrappers::JS_GetPropertyById;
-use js::rust::HandleValue;
-use js::rust::IdVector;
-use js::rust::MutableHandleValue;
-use std::ops::Deref;
-
-/// The `MozMap` (open-ended dictionary) type.
-#[derive(Clone, JSTraceable)]
-pub struct MozMap<T> {
-    map: IndexMap<DOMString, T>,
-}
-
-impl<T> MozMap<T> {
-    /// Create an empty `MozMap`.
-    pub fn new() -> Self {
-        MozMap {
-            map: IndexMap::new(),
-        }
-    }
-}
-
-impl<T> Deref for MozMap<T> {
-    type Target = IndexMap<DOMString, T>;
-
-    fn deref(&self) -> &IndexMap<DOMString, T> {
-        &self.map
-    }
-}
-
-impl<T, C> FromJSValConvertible for MozMap<T>
-where
-    T: FromJSValConvertible<Config = C>,
-    C: Clone,
-{
-    type Config = C;
-    unsafe fn from_jsval(
-        cx: *mut JSContext,
-        value: HandleValue,
-        config: C,
-    ) -> Result<ConversionResult<Self>, ()> {
-        if !value.is_object() {
-            return Ok(ConversionResult::Failure(
-                "MozMap value was not an object".into(),
-            ));
-        }
-
-        rooted!(in(cx) let object = value.to_object());
-        let ids = IdVector::new(cx);
-        if !GetPropertyKeys(
-            cx,
-            object.handle(),
-            JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS,
-            ids.get(),
-        ) {
-            // TODO: can GetPropertyKeys fail?
-            // (it does so if the object has duplicate keys)
-            // https://github.com/servo/servo/issues/21462
-            report_pending_exception(cx, false);
-            return Ok(ConversionResult::Failure(
-                "Getting MozMap value property keys failed".into(),
-            ));
-        }
-
-        let mut map = IndexMap::new();
-        for id in &*ids {
-            rooted!(in(cx) let id = *id);
-
-            rooted!(in(cx) let mut property = UndefinedValue());
-            if !JS_GetPropertyById(cx, object.handle(), id.handle(), property.handle_mut()) {
-                return Err(());
-            }
-
-            let property = match T::from_jsval(cx, property.handle(), config.clone())? {
-                ConversionResult::Success(property) => property,
-                ConversionResult::Failure(message) => {
-                    return Ok(ConversionResult::Failure(message))
-                },
-            };
-
-            // TODO: Is this guaranteed to succeed?
-            // https://github.com/servo/servo/issues/21463
-            if let Some(key) = jsid_to_string(cx, id.handle()) {
-                map.insert(key, property);
-            }
-        }
-
-        Ok(ConversionResult::Success(MozMap { map: map }))
-    }
-}
-
-impl<T: ToJSValConvertible> ToJSValConvertible for MozMap<T> {
-    #[inline]
-    unsafe fn to_jsval(&self, cx: *mut JSContext, mut rval: MutableHandleValue) {
-        rooted!(in(cx) let js_object = JS_NewPlainObject(cx));
-        assert!(!js_object.handle().is_null());
-
-        rooted!(in(cx) let mut js_value = UndefinedValue());
-        for (key, value) in &self.map {
-            let key = key.encode_utf16().collect::<Vec<_>>();
-            value.to_jsval(cx, js_value.handle_mut());
-
-            assert!(JS_DefineUCProperty2(
-                cx,
-                js_object.handle(),
-                key.as_ptr(),
-                key.len(),
-                js_value.handle(),
-                JSPROP_ENUMERATE as u32
-            ));
-        }
-
-        rval.set(ObjectValue(js_object.handle().get()));
-    }
-}
diff --git a/components/script/dom/bindings/record.rs b/components/script/dom/bindings/record.rs
new file mode 100644
index 00000000000..86453b59fc3
--- /dev/null
+++ b/components/script/dom/bindings/record.rs
@@ -0,0 +1,199 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! The `Record` (open-ended dictionary) type.
+
+use crate::dom::bindings::conversions::jsid_to_string;
+use crate::dom::bindings::str::{ByteString, DOMString, USVString};
+use indexmap::IndexMap;
+use js::conversions::{ConversionResult, FromJSValConvertible, ToJSValConvertible};
+use js::jsapi::HandleId as RawHandleId;
+use js::jsapi::JSContext;
+use js::jsapi::JS_NewPlainObject;
+use js::jsapi::PropertyDescriptor;
+use js::jsapi::JSITER_HIDDEN;
+use js::jsapi::JSITER_OWNONLY;
+use js::jsapi::JSITER_SYMBOLS;
+use js::jsapi::JSPROP_ENUMERATE;
+use js::jsval::ObjectValue;
+use js::jsval::UndefinedValue;
+use js::rust::wrappers::GetPropertyKeys;
+use js::rust::wrappers::JS_DefineUCProperty2;
+use js::rust::wrappers::JS_GetOwnPropertyDescriptorById;
+use js::rust::wrappers::JS_GetPropertyById;
+use js::rust::wrappers::JS_IdToValue;
+use js::rust::HandleId;
+use js::rust::HandleValue;
+use js::rust::IdVector;
+use js::rust::MutableHandleValue;
+use std::cmp::Eq;
+use std::hash::Hash;
+use std::marker::Sized;
+use std::ops::Deref;
+
+pub trait RecordKey: Eq + Hash + Sized {
+    fn to_utf16_vec(&self) -> Vec<u16>;
+    unsafe fn from_id(cx: *mut JSContext, id: HandleId) -> Result<ConversionResult<Self>, ()>;
+}
+
+impl RecordKey for DOMString {
+    fn to_utf16_vec(&self) -> Vec<u16> {
+        self.encode_utf16().collect::<Vec<_>>()
+    }
+
+    unsafe fn from_id(cx: *mut JSContext, id: HandleId) -> Result<ConversionResult<Self>, ()> {
+        match jsid_to_string(cx, id) {
+            Some(s) => Ok(ConversionResult::Success(s)),
+            None => Ok(ConversionResult::Failure("Failed to get DOMString".into())),
+        }
+    }
+}
+
+impl RecordKey for USVString {
+    fn to_utf16_vec(&self) -> Vec<u16> {
+        self.0.encode_utf16().collect::<Vec<_>>()
+    }
+
+    unsafe fn from_id(cx: *mut JSContext, id: HandleId) -> Result<ConversionResult<Self>, ()> {
+        rooted!(in(cx) let mut jsid_value = UndefinedValue());
+        let raw_id: RawHandleId = id.into();
+        JS_IdToValue(cx, *raw_id.ptr, jsid_value.handle_mut());
+
+        USVString::from_jsval(cx, jsid_value.handle(), ())
+    }
+}
+
+impl RecordKey for ByteString {
+    fn to_utf16_vec(&self) -> Vec<u16> {
+        self.iter().map(|&x| x as u16).collect::<Vec<u16>>()
+    }
+
+    unsafe fn from_id(cx: *mut JSContext, id: HandleId) -> Result<ConversionResult<Self>, ()> {
+        rooted!(in(cx) let mut jsid_value = UndefinedValue());
+        let raw_id: RawHandleId = id.into();
+        JS_IdToValue(cx, *raw_id.ptr, jsid_value.handle_mut());
+
+        ByteString::from_jsval(cx, jsid_value.handle(), ())
+    }
+}
+
+/// The `Record` (open-ended dictionary) type.
+#[derive(Clone, JSTraceable)]
+pub struct Record<K: RecordKey, V> {
+    map: IndexMap<K, V>,
+}
+
+impl<K: RecordKey, V> Record<K, V> {
+    /// Create an empty `Record`.
+    pub fn new() -> Self {
+        Record {
+            map: IndexMap::new(),
+        }
+    }
+}
+
+impl<K: RecordKey, V> Deref for Record<K, V> {
+    type Target = IndexMap<K, V>;
+
+    fn deref(&self) -> &IndexMap<K, V> {
+        &self.map
+    }
+}
+
+impl<K, V, C> FromJSValConvertible for Record<K, V>
+where
+    K: RecordKey,
+    V: FromJSValConvertible<Config = C>,
+    C: Clone,
+{
+    type Config = C;
+    unsafe fn from_jsval(
+        cx: *mut JSContext,
+        value: HandleValue,
+        config: C,
+    ) -> Result<ConversionResult<Self>, ()> {
+        if !value.is_object() {
+            return Ok(ConversionResult::Failure(
+                "Record value was not an object".into(),
+            ));
+        }
+
+        rooted!(in(cx) let object = value.to_object());
+        let ids = IdVector::new(cx);
+        if !GetPropertyKeys(
+            cx,
+            object.handle(),
+            JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS,
+            ids.get(),
+        ) {
+            return Err(());
+        }
+
+        let mut map = IndexMap::new();
+        for id in &*ids {
+            rooted!(in(cx) let id = *id);
+            rooted!(in(cx) let mut desc = PropertyDescriptor::default());
+
+            if !JS_GetOwnPropertyDescriptorById(cx, object.handle(), id.handle(), desc.handle_mut())
+            {
+                return Err(());
+            }
+
+            if (JSPROP_ENUMERATE as u32) & desc.attrs == 0 {
+                continue;
+            }
+
+            let key = match K::from_id(cx, id.handle())? {
+                ConversionResult::Success(key) => key,
+                ConversionResult::Failure(message) => {
+                    return Ok(ConversionResult::Failure(message))
+                },
+            };
+
+            rooted!(in(cx) let mut property = UndefinedValue());
+            if !JS_GetPropertyById(cx, object.handle(), id.handle(), property.handle_mut()) {
+                return Err(());
+            }
+
+            let property = match V::from_jsval(cx, property.handle(), config.clone())? {
+                ConversionResult::Success(property) => property,
+                ConversionResult::Failure(message) => {
+                    return Ok(ConversionResult::Failure(message))
+                },
+            };
+            map.insert(key, property);
+        }
+
+        Ok(ConversionResult::Success(Record { map: map }))
+    }
+}
+
+impl<K, V> ToJSValConvertible for Record<K, V>
+where
+    K: RecordKey,
+    V: ToJSValConvertible,
+{
+    #[inline]
+    unsafe fn to_jsval(&self, cx: *mut JSContext, mut rval: MutableHandleValue) {
+        rooted!(in(cx) let js_object = JS_NewPlainObject(cx));
+        assert!(!js_object.handle().is_null());
+
+        rooted!(in(cx) let mut js_value = UndefinedValue());
+        for (key, value) in &self.map {
+            let key = key.to_utf16_vec();
+            value.to_jsval(cx, js_value.handle_mut());
+
+            assert!(JS_DefineUCProperty2(
+                cx,
+                js_object.handle(),
+                key.as_ptr(),
+                key.len(),
+                js_value.handle(),
+                JSPROP_ENUMERATE as u32
+            ));
+        }
+
+        rval.set(ObjectValue(js_object.handle().get()));
+    }
+}
diff --git a/components/script/dom/bindings/str.rs b/components/script/dom/bindings/str.rs
index ad4ce8bc621..38091fcf19e 100644
--- a/components/script/dom/bindings/str.rs
+++ b/components/script/dom/bindings/str.rs
@@ -74,7 +74,7 @@ impl ops::Deref for ByteString {
 
 /// A string that is constructed from a UCS-2 buffer by replacing invalid code
 /// points with the replacement character.
-#[derive(Clone, Default, Eq, MallocSizeOf, Ord, PartialEq, PartialOrd)]
+#[derive(Clone, Default, Eq, Hash, MallocSizeOf, Ord, PartialEq, PartialOrd)]
 pub struct USVString(pub String);
 
 impl Borrow<str> for USVString {
diff --git a/components/script/dom/headers.rs b/components/script/dom/headers.rs
index 2f2af810df8..017cde9268a 100644
--- a/components/script/dom/headers.rs
+++ b/components/script/dom/headers.rs
@@ -215,11 +215,9 @@ impl Headers {
                 }
                 Ok(())
             },
-            Some(HeadersInit::StringByteStringRecord(m)) => {
+            Some(HeadersInit::ByteStringByteStringRecord(m)) => {
                 for (key, value) in m.iter() {
-                    let key_vec = key.as_ref().to_string().into();
-                    let headers_key = ByteString::new(key_vec);
-                    self.Append(headers_key, value.clone())?;
+                    self.Append(key.clone(), value.clone())?;
                 }
                 Ok(())
             },
diff --git a/components/script/dom/request.rs b/components/script/dom/request.rs
index b777dd0cb56..5393288c633 100644
--- a/components/script/dom/request.rs
+++ b/components/script/dom/request.rs
@@ -311,9 +311,10 @@ impl Request {
                         init_sequence.clone(),
                     )))?;
                 },
-                &HeadersInit::StringByteStringRecord(ref init_map) => {
-                    headers_copy
-                        .fill(Some(HeadersInit::StringByteStringRecord(init_map.clone())))?;
+                &HeadersInit::ByteStringByteStringRecord(ref init_map) => {
+                    headers_copy.fill(Some(HeadersInit::ByteStringByteStringRecord(
+                        init_map.clone(),
+                    )))?;
                 },
             }
         }
@@ -859,8 +860,8 @@ impl Clone for HeadersInit {
             &HeadersInit::ByteStringSequenceSequence(ref b) => {
                 HeadersInit::ByteStringSequenceSequence(b.clone())
             },
-            &HeadersInit::StringByteStringRecord(ref m) => {
-                HeadersInit::StringByteStringRecord(m.clone())
+            &HeadersInit::ByteStringByteStringRecord(ref m) => {
+                HeadersInit::ByteStringByteStringRecord(m.clone())
             },
         }
     }
diff --git a/components/script/dom/testbinding.rs b/components/script/dom/testbinding.rs
index 607c97085f1..31972afe948 100644
--- a/components/script/dom/testbinding.rs
+++ b/components/script/dom/testbinding.rs
@@ -36,8 +36,8 @@ use crate::dom::bindings::codegen::UnionTypes::{
     StringOrUnsignedLong, StringSequenceOrUnsignedLong,
 };
 use crate::dom::bindings::error::{Error, Fallible};
-use crate::dom::bindings::mozmap::MozMap;
 use crate::dom::bindings::num::Finite;
+use crate::dom::bindings::record::Record;
 use crate::dom::bindings::refcounted::TrustedPromise;
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
 use crate::dom::bindings::root::DomRoot;
@@ -894,50 +894,64 @@ impl TestBindingMethods for TestBinding {
     fn FuncControlledMethodDisabled(&self) {}
     fn FuncControlledMethodEnabled(&self) {}
 
-    fn PassMozMap(&self, _: MozMap<i32>) {}
-    fn PassNullableMozMap(&self, _: Option<MozMap<i32>>) {}
-    fn PassMozMapOfNullableInts(&self, _: MozMap<Option<i32>>) {}
-    fn PassOptionalMozMapOfNullableInts(&self, _: Option<MozMap<Option<i32>>>) {}
-    fn PassOptionalNullableMozMapOfNullableInts(&self, _: Option<Option<MozMap<Option<i32>>>>) {}
-    fn PassCastableObjectMozMap(&self, _: MozMap<DomRoot<TestBinding>>) {}
-    fn PassNullableCastableObjectMozMap(&self, _: MozMap<Option<DomRoot<TestBinding>>>) {}
-    fn PassCastableObjectNullableMozMap(&self, _: Option<MozMap<DomRoot<TestBinding>>>) {}
-    fn PassNullableCastableObjectNullableMozMap(
+    fn PassRecord(&self, _: Record<DOMString, i32>) {}
+    fn PassRecordWithUSVStringKey(&self, _: Record<USVString, i32>) {}
+    fn PassRecordWithByteStringKey(&self, _: Record<ByteString, i32>) {}
+    fn PassNullableRecord(&self, _: Option<Record<DOMString, i32>>) {}
+    fn PassRecordOfNullableInts(&self, _: Record<DOMString, Option<i32>>) {}
+    fn PassOptionalRecordOfNullableInts(&self, _: Option<Record<DOMString, Option<i32>>>) {}
+    fn PassOptionalNullableRecordOfNullableInts(
         &self,
-        _: Option<MozMap<Option<DomRoot<TestBinding>>>>,
+        _: Option<Option<Record<DOMString, Option<i32>>>>,
     ) {
     }
-    fn PassOptionalMozMap(&self, _: Option<MozMap<i32>>) {}
-    fn PassOptionalNullableMozMap(&self, _: Option<Option<MozMap<i32>>>) {}
-    fn PassOptionalNullableMozMapWithDefaultValue(&self, _: Option<MozMap<i32>>) {}
-    fn PassOptionalObjectMozMap(&self, _: Option<MozMap<DomRoot<TestBinding>>>) {}
-    fn PassStringMozMap(&self, _: MozMap<DOMString>) {}
-    fn PassByteStringMozMap(&self, _: MozMap<ByteString>) {}
-    fn PassMozMapOfMozMaps(&self, _: MozMap<MozMap<i32>>) {}
-    fn PassMozMapUnion(&self, _: UnionTypes::LongOrStringByteStringRecord) {}
-    fn PassMozMapUnion2(&self, _: UnionTypes::TestBindingOrStringByteStringRecord) {}
-    fn PassMozMapUnion3(
+    fn PassCastableObjectRecord(&self, _: Record<DOMString, DomRoot<TestBinding>>) {}
+    fn PassNullableCastableObjectRecord(&self, _: Record<DOMString, Option<DomRoot<TestBinding>>>) {
+    }
+    fn PassCastableObjectNullableRecord(&self, _: Option<Record<DOMString, DomRoot<TestBinding>>>) {
+    }
+    fn PassNullableCastableObjectNullableRecord(
+        &self,
+        _: Option<Record<DOMString, Option<DomRoot<TestBinding>>>>,
+    ) {
+    }
+    fn PassOptionalRecord(&self, _: Option<Record<DOMString, i32>>) {}
+    fn PassOptionalNullableRecord(&self, _: Option<Option<Record<DOMString, i32>>>) {}
+    fn PassOptionalNullableRecordWithDefaultValue(&self, _: Option<Record<DOMString, i32>>) {}
+    fn PassOptionalObjectRecord(&self, _: Option<Record<DOMString, DomRoot<TestBinding>>>) {}
+    fn PassStringRecord(&self, _: Record<DOMString, DOMString>) {}
+    fn PassByteStringRecord(&self, _: Record<DOMString, ByteString>) {}
+    fn PassRecordOfRecords(&self, _: Record<DOMString, Record<DOMString, i32>>) {}
+    fn PassRecordUnion(&self, _: UnionTypes::LongOrStringByteStringRecord) {}
+    fn PassRecordUnion2(&self, _: UnionTypes::TestBindingOrStringByteStringRecord) {}
+    fn PassRecordUnion3(
         &self,
         _: UnionTypes::TestBindingOrByteStringSequenceSequenceOrStringByteStringRecord,
     ) {
     }
-    fn ReceiveMozMap(&self) -> MozMap<i32> {
-        MozMap::new()
+    fn ReceiveRecord(&self) -> Record<DOMString, i32> {
+        Record::new()
+    }
+    fn ReceiveRecordWithUSVStringKey(&self) -> Record<USVString, i32> {
+        Record::new()
+    }
+    fn ReceiveRecordWithByteStringKey(&self) -> Record<ByteString, i32> {
+        Record::new()
     }
-    fn ReceiveNullableMozMap(&self) -> Option<MozMap<i32>> {
-        Some(MozMap::new())
+    fn ReceiveNullableRecord(&self) -> Option<Record<DOMString, i32>> {
+        Some(Record::new())
     }
-    fn ReceiveMozMapOfNullableInts(&self) -> MozMap<Option<i32>> {
-        MozMap::new()
+    fn ReceiveRecordOfNullableInts(&self) -> Record<DOMString, Option<i32>> {
+        Record::new()
     }
-    fn ReceiveNullableMozMapOfNullableInts(&self) -> Option<MozMap<Option<i32>>> {
-        Some(MozMap::new())
+    fn ReceiveNullableRecordOfNullableInts(&self) -> Option<Record<DOMString, Option<i32>>> {
+        Some(Record::new())
     }
-    fn ReceiveMozMapOfMozMaps(&self) -> MozMap<MozMap<i32>> {
-        MozMap::new()
+    fn ReceiveRecordOfRecords(&self) -> Record<DOMString, Record<DOMString, i32>> {
+        Record::new()
     }
-    fn ReceiveAnyMozMap(&self) -> MozMap<JSVal> {
-        MozMap::new()
+    fn ReceiveAnyRecord(&self) -> Record<DOMString, JSVal> {
+        Record::new()
     }
 
     #[allow(unrooted_must_root)]
diff --git a/components/script/dom/webidls/Headers.webidl b/components/script/dom/webidls/Headers.webidl
index 88e9a14c8d6..cc85136eb41 100644
--- a/components/script/dom/webidls/Headers.webidl
+++ b/components/script/dom/webidls/Headers.webidl
@@ -4,7 +4,7 @@
 
 // https://fetch.spec.whatwg.org/#headers-class
 
-typedef (Headers or sequence<sequence<ByteString>> or record<DOMString, ByteString>) HeadersInit;
+typedef (Headers or sequence<sequence<ByteString>> or record<ByteString, ByteString>) HeadersInit;
 
 [Exposed=(Window,Worker)]
 interface Headers {
diff --git a/components/script/dom/webidls/TestBinding.webidl b/components/script/dom/webidls/TestBinding.webidl
index 0621be01858..9c3fdc02638 100644
--- a/components/script/dom/webidls/TestBinding.webidl
+++ b/components/script/dom/webidls/TestBinding.webidl
@@ -461,33 +461,37 @@ interface TestBinding {
   sequence<sequence<long>> returnSequenceSequence();
   void passUnionSequenceSequence((long or sequence<sequence<long>>) seq);
 
-  void passMozMap(record<DOMString, long> arg);
-  void passNullableMozMap(record<DOMString, long>? arg);
-  void passMozMapOfNullableInts(record<DOMString, long?> arg);
-  void passOptionalMozMapOfNullableInts(optional record<DOMString, long?> arg);
-  void passOptionalNullableMozMapOfNullableInts(optional record<DOMString, long?>? arg);
-  void passCastableObjectMozMap(record<DOMString, TestBinding> arg);
-  void passNullableCastableObjectMozMap(record<DOMString, TestBinding?> arg);
-  void passCastableObjectNullableMozMap(record<DOMString, TestBinding>? arg);
-  void passNullableCastableObjectNullableMozMap(record<DOMString, TestBinding?>? arg);
-  void passOptionalMozMap(optional record<DOMString, long> arg);
-  void passOptionalNullableMozMap(optional record<DOMString, long>? arg);
-  void passOptionalNullableMozMapWithDefaultValue(optional record<DOMString, long>? arg = null);
-  void passOptionalObjectMozMap(optional record<DOMString, TestBinding> arg);
-  void passStringMozMap(record<DOMString, DOMString> arg);
-  void passByteStringMozMap(record<DOMString, ByteString> arg);
-  void passMozMapOfMozMaps(record<DOMString, record<DOMString, long>> arg);
-
-  void passMozMapUnion((long or record<DOMString, ByteString>) init);
-  void passMozMapUnion2((TestBinding or record<DOMString, ByteString>) init);
-  void passMozMapUnion3((TestBinding or sequence<sequence<ByteString>> or record<DOMString, ByteString>) init);
-
-  record<DOMString, long> receiveMozMap();
-  record<DOMString, long>? receiveNullableMozMap();
-  record<DOMString, long?> receiveMozMapOfNullableInts();
-  record<DOMString, long?>? receiveNullableMozMapOfNullableInts();
-  record<DOMString, record<DOMString, long>> receiveMozMapOfMozMaps();
-  record<DOMString, any> receiveAnyMozMap();
+  void passRecord(record<DOMString, long> arg);
+  void passRecordWithUSVStringKey(record<USVString, long> arg);
+  void passRecordWithByteStringKey(record<ByteString, long> arg);
+  void passNullableRecord(record<DOMString, long>? arg);
+  void passRecordOfNullableInts(record<DOMString, long?> arg);
+  void passOptionalRecordOfNullableInts(optional record<DOMString, long?> arg);
+  void passOptionalNullableRecordOfNullableInts(optional record<DOMString, long?>? arg);
+  void passCastableObjectRecord(record<DOMString, TestBinding> arg);
+  void passNullableCastableObjectRecord(record<DOMString, TestBinding?> arg);
+  void passCastableObjectNullableRecord(record<DOMString, TestBinding>? arg);
+  void passNullableCastableObjectNullableRecord(record<DOMString, TestBinding?>? arg);
+  void passOptionalRecord(optional record<DOMString, long> arg);
+  void passOptionalNullableRecord(optional record<DOMString, long>? arg);
+  void passOptionalNullableRecordWithDefaultValue(optional record<DOMString, long>? arg = null);
+  void passOptionalObjectRecord(optional record<DOMString, TestBinding> arg);
+  void passStringRecord(record<DOMString, DOMString> arg);
+  void passByteStringRecord(record<DOMString, ByteString> arg);
+  void passRecordOfRecords(record<DOMString, record<DOMString, long>> arg);
+
+  void passRecordUnion((long or record<DOMString, ByteString>) init);
+  void passRecordUnion2((TestBinding or record<DOMString, ByteString>) init);
+  void passRecordUnion3((TestBinding or sequence<sequence<ByteString>> or record<DOMString, ByteString>) init);
+
+  record<DOMString, long> receiveRecord();
+  record<USVString, long> receiveRecordWithUSVStringKey();
+  record<ByteString, long> receiveRecordWithByteStringKey();
+  record<DOMString, long>? receiveNullableRecord();
+  record<DOMString, long?> receiveRecordOfNullableInts();
+  record<DOMString, long?>? receiveNullableRecordOfNullableInts();
+  record<DOMString, record<DOMString, long>> receiveRecordOfRecords();
+  record<DOMString, any> receiveAnyRecord();
 
   static attribute boolean booleanAttributeStatic;
   static void receiveVoidStatic();
diff --git a/tests/wpt/metadata/fetch/api/headers/headers-record.html.ini b/tests/wpt/metadata/fetch/api/headers/headers-record.html.ini
deleted file mode 100644
index 999e0b2c586..00000000000
--- a/tests/wpt/metadata/fetch/api/headers/headers-record.html.ini
+++ /dev/null
@@ -1,29 +0,0 @@
-[headers-record.html]
-  type: testharness
-  [Basic operation with one property]
-    expected: FAIL
-
-  [Basic operation with one property and a proto]
-    expected: FAIL
-
-  [Correct operation ordering with two properties]
-    expected: FAIL
-
-  [Correct operation ordering with two properties one of which has an invalid name]
-    expected: FAIL
-
-  [Correct operation ordering with two properties one of which has an invalid value]
-    expected: FAIL
-
-  [Correct operation ordering with non-enumerable properties]
-    expected: FAIL
-
-  [Correct operation ordering with undefined descriptors]
-    expected: FAIL
-
-  [Basic operation with Symbol keys]
-    expected: FAIL
-
-  [Operation with non-enumerable Symbol keys]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/url/urlsearchparams-constructor.any.js.ini b/tests/wpt/metadata/url/urlsearchparams-constructor.any.js.ini
deleted file mode 100644
index 09df91b6479..00000000000
--- a/tests/wpt/metadata/url/urlsearchparams-constructor.any.js.ini
+++ /dev/null
@@ -1,8 +0,0 @@
-[urlsearchparams-constructor.any.worker.html]
-  [URLSearchParams constructor, DOMException as argument]
-    expected: FAIL
-
-
-[urlsearchparams-constructor.any.html]
-  [URLSearchParams constructor, DOMException as argument]
-    expected: FAIL