diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index ec1a0a7ec15..e6a4c5c1365 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -4321,10 +4321,12 @@ class CGDOMJSProxyHandler_getOwnPropertyDescriptor(CGAbstractExternMethod):
             get = "let index = get_array_index_from_id(cx, id);\n"
 
         if indexedGetter:
-            readonly = toStringBool(self.descriptor.operations['IndexedSetter'] is None)
+            attrs = "JSPROP_ENUMERATE"
+            if self.descriptor.operations['IndexedSetter'] is None:
+                attrs += " | JSPROP_READONLY"
             fillDescriptor = ("desc.get().value = result_root.ptr;\n"
                               "fill_property_descriptor(&mut *desc.ptr, *proxy.ptr, %s);\n"
-                              "return true;" % readonly)
+                              "return true;" % attrs)
             templateValues = {
                 'jsvalRef': 'result_root.handle_mut()',
                 'successCode': fillDescriptor,
@@ -4338,10 +4340,12 @@ class CGDOMJSProxyHandler_getOwnPropertyDescriptor(CGAbstractExternMethod):
 
         namedGetter = self.descriptor.operations['NamedGetter']
         if namedGetter:
-            readonly = toStringBool(self.descriptor.operations['NamedSetter'] is None)
+            attrs = "JSPROP_ENUMERATE"
+            if self.descriptor.operations['IndexedSetter'] is None:
+                attrs += " | JSPROP_READONLY"
             fillDescriptor = ("desc.get().value = result_root.ptr;\n"
                               "fill_property_descriptor(&mut *desc.ptr, *proxy.ptr, %s);\n"
-                              "return true;" % readonly)
+                              "return true;" % attrs)
             templateValues = {
                 'jsvalRef': 'result_root.handle_mut()',
                 'successCode': fillDescriptor,
diff --git a/components/script/dom/bindings/proxyhandler.rs b/components/script/dom/bindings/proxyhandler.rs
index e85d93ce326..3d5a841edb3 100644
--- a/components/script/dom/bindings/proxyhandler.rs
+++ b/components/script/dom/bindings/proxyhandler.rs
@@ -8,6 +8,7 @@
 
 use dom::bindings::conversions::is_dom_proxy;
 use dom::bindings::utils::delete_property_by_id;
+use js::JSPROP_GETTER;
 use js::glue::GetProxyExtra;
 use js::glue::InvokeGetOwnPropertyDescriptor;
 use js::glue::{GetProxyHandler, SetProxyExtra};
@@ -18,7 +19,6 @@ use js::jsapi::{JSContext, JSObject, JSPropertyDescriptor};
 use js::jsapi::{JSErrNum, JS_StrictPropertyStub};
 use js::jsapi::{JS_DefinePropertyById6, JS_NewObjectWithGivenProto};
 use js::jsval::ObjectValue;
-use js::{JSPROP_ENUMERATE, JSPROP_GETTER, JSPROP_READONLY};
 use libc;
 use std::{mem, ptr};
 
@@ -135,9 +135,9 @@ pub fn ensure_expando_object(cx: *mut JSContext, obj: HandleObject) -> *mut JSOb
 /// and writable if `readonly` is true.
 pub fn fill_property_descriptor(desc: &mut JSPropertyDescriptor,
                                 obj: *mut JSObject,
-                                readonly: bool) {
+                                attrs: u32) {
     desc.obj = obj;
-    desc.attrs = if readonly { JSPROP_READONLY } else { 0 } | JSPROP_ENUMERATE;
+    desc.attrs = attrs;
     desc.getter = None;
     desc.setter = None;
 }
diff --git a/components/script/dom/browsingcontext.rs b/components/script/dom/browsingcontext.rs
index 7149a365800..c88b4e053e3 100644
--- a/components/script/dom/browsingcontext.rs
+++ b/components/script/dom/browsingcontext.rs
@@ -12,15 +12,15 @@ use dom::bindings::utils::get_array_index_from_id;
 use dom::document::Document;
 use dom::element::Element;
 use dom::window::Window;
-use js::JSCLASS_IS_GLOBAL;
-use js::glue::{CreateWrapperProxyHandler, GetProxyPrivate, NewWindowProxy};
-use js::glue::{ProxyTraps, SetProxyExtra};
+use js::glue::{CreateWrapperProxyHandler, ProxyTraps, NewWindowProxy};
+use js::glue::{GetProxyPrivate, SetProxyExtra};
 use js::jsapi::{Handle, HandleId, HandleObject, JSAutoCompartment, JSAutoRequest, JSContext};
 use js::jsapi::{JSErrNum, JSObject, JSPropertyDescriptor, JS_DefinePropertyById6};
 use js::jsapi::{JS_ForwardGetPropertyTo, JS_ForwardSetPropertyTo, JS_GetClass};
 use js::jsapi::{JS_GetOwnPropertyDescriptorById, JS_HasPropertyById, MutableHandle};
 use js::jsapi::{MutableHandleValue, ObjectOpResult, RootedObject, RootedValue};
-use js::jsval::{ObjectValue, PrivateValue, UndefinedValue};
+use js::jsval::{ObjectValue, UndefinedValue, PrivateValue};
+use js::{JSCLASS_IS_GLOBAL, JSPROP_READONLY};
 
 #[dom_struct]
 pub struct BrowsingContext {
@@ -138,7 +138,7 @@ unsafe extern "C" fn getOwnPropertyDescriptor(cx: *mut JSContext,
         let mut val = RootedValue::new(cx, UndefinedValue());
         window.to_jsval(cx, val.handle_mut());
         (*desc.ptr).value = val.ptr;
-        fill_property_descriptor(&mut *desc.ptr, *proxy.ptr, true);
+        fill_property_descriptor(&mut *desc.ptr, *proxy.ptr, JSPROP_READONLY);
         return true;
     }