Auto merge of #8751 - nox:rm-prototype-slot, r=Ms2ger

Remove unused slot in prototype object (fixes #8588)

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1 files changed, 0 insertions, 19 deletions

diff --git a/components/script/dom/bindings/utils.rs b/components/script/dom/bindings/utils.rs
index 775df6a45aa..97d5bb12eba 100644
--- a/components/script/dom/bindings/utils.rs
+++ b/components/script/dom/bindings/utils.rs
@@ -78,11 +78,6 @@ impl GlobalStaticData {
     }
 }
 
-// NOTE: This is baked into the Ion JIT as 0 in codegen for LGetDOMProperty and
-// LSetDOMProperty. Those constants need to be changed accordingly if this value
-// changes.
-const DOM_PROTO_INSTANCE_CLASS_SLOT: u32 = 0;
-
 /// The index of the slot that contains a reference to the ProtoOrIfaceArray.
 // All DOM globals must have a slot at DOM_PROTOTYPE_SLOT.
 pub const DOM_PROTOTYPE_SLOT: u32 = js::JSCLASS_GLOBAL_SLOT_COUNT;
@@ -210,25 +205,11 @@ pub fn do_create_interface_objects(cx: *mut JSContext,
                                    proto_class: Option<&'static JSClass>,
                                    constructor: Option<(NonNullJSNative, &'static str, u32)>,
                                    named_constructors: &[(NonNullJSNative, &'static str, u32)],
-                                   dom_class: Option<&'static DOMClass>,
                                    members: &'static NativeProperties,
                                    rval: MutableHandleObject) {
     assert!(rval.get().is_null());
     if let Some(proto_class) = proto_class {
         create_interface_prototype_object(cx, proto_proto, proto_class, members, rval);
-
-        if !rval.get().is_null() {
-            let dom_class_ptr = match dom_class {
-                Some(dom_class) => dom_class as *const DOMClass as *const libc::c_void,
-                None => ptr::null() as *const libc::c_void,
-            };
-
-            unsafe {
-                JS_SetReservedSlot(rval.get(),
-                                   DOM_PROTO_INSTANCE_CLASS_SLOT,
-                                   PrivateValue(dom_class_ptr));
-            }
-        }
     }
 
     if let Some((native, name, nargs)) = constructor {