Auto merge of #18875 - servo:stable-js, r=nox,jdm

Remove the need for rust-mozjs to use unstable Rust features

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1 files changed, 13 insertions, 2 deletions

diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index 075f681308e..e27813d20f9 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -34,6 +34,7 @@
 
 use dom::bindings::error::{Error, Fallible};
 use dom::bindings::inheritance::Castable;
+use dom::bindings::nonnull::NonNullJSObjectPtr;
 use dom::bindings::num::Finite;
 use dom::bindings::reflector::{DomObject, Reflector};
 use dom::bindings::root::DomRoot;
@@ -53,7 +54,7 @@ use js::jsapi::{JS_GetLatin1StringCharsAndLength, JS_GetProperty, JS_GetReserved
 use js::jsapi::{JS_GetTwoByteStringCharsAndLength, JS_IsArrayObject, JS_IsExceptionPending};
 use js::jsapi::{JS_NewStringCopyN, JS_StringHasLatin1Chars, MutableHandleValue};
 use js::jsval::{ObjectValue, StringValue, UndefinedValue};
-use js::rust::{ToString, get_object_class, is_dom_class, is_dom_object, maybe_wrap_value};
+use js::rust::{ToString, get_object_class, is_dom_class, is_dom_object, maybe_wrap_value, maybe_wrap_object_value};
 use libc;
 use num_traits::Float;
 use servo_config::opts;
@@ -66,9 +67,19 @@ pub trait IDLInterface {
 }
 
 /// A trait to mark an IDL interface as deriving from another one.
-#[rustc_on_unimplemented = "The IDL interface `{Self}` is not derived from `{T}`."]
+#[cfg_attr(feature = "unstable",
+           rustc_on_unimplemented = "The IDL interface `{Self}` is not derived from `{T}`.")]
 pub trait DerivedFrom<T: Castable>: Castable {}
 
+// https://heycam.github.io/webidl/#es-object
+impl ToJSValConvertible for NonNullJSObjectPtr {
+    #[inline]
+    unsafe fn to_jsval(&self, cx: *mut JSContext, rval: MutableHandleValue) {
+        rval.set(ObjectValue(self.get()));
+        maybe_wrap_object_value(cx, rval);
+    }
+}
+
 impl<T: Float + ToJSValConvertible> ToJSValConvertible for Finite<T> {
     #[inline]
     unsafe fn to_jsval(&self, cx: *mut JSContext, rval: MutableHandleValue) {