--- a/js/src/jsfriendapi.cpp
+++ b/js/src/jsfriendapi.cpp
@@ -1032,8 +1032,25 @@ js::AutoCTypesActivityCallback::AutoCTyp
                                                            MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL)
   : cx(cx), callback(cx->runtime->ctypesActivityCallback), endType(endType)
 {
     MOZ_GUARD_OBJECT_NOTIFIER_INIT;
 
     if (callback)
         callback(cx, beginType);
 }
+
+JS_FRIEND_API(JSBool)
+js_DefineOwnProperty(JSContext *cx, JSObject *objArg, jsid idArg,
+                     const js::PropertyDescriptor& descriptor, JSBool *bp)
+{
+    RootedObject obj(cx, objArg);
+    RootedId id(cx, idArg);
+    JS_ASSERT(cx->runtime->heapState == js::Idle);
+    CHECK_REQUEST(cx);
+    assertSameCompartment(cx, obj, id, descriptor.value);
+    if (descriptor.attrs & JSPROP_GETTER)
+        assertSameCompartment(cx, CastAsObjectJsval(descriptor.getter));
+    if (descriptor.attrs & JSPROP_SETTER)
+        assertSameCompartment(cx, CastAsObjectJsval(descriptor.setter));
+
+    return js_DefineOwnProperty(cx, HandleObject(obj), id, descriptor, bp);
+}

--- a/js/src/jsfriendapi.h
+++ b/js/src/jsfriendapi.h
@@ -1435,9 +1435,13 @@ class JS_FRIEND_API(AutoCTypesActivityCa
 extern JS_FRIEND_API(void)
 assertEnteredPolicy(JSContext *cx, JSObject *obj, jsid id);
 #else
 inline void assertEnteredPolicy(JSContext *cx, JSObject *obj, jsid id) {};
 #endif
 
 } /* namespace js */
 
+extern JS_FRIEND_API(JSBool)
+js_DefineOwnProperty(JSContext *cx, JSObject *objArg, jsid idArg,
+                     const js::PropertyDescriptor& descriptor, JSBool *bp);
+
 #endif /* jsfriendapi_h___ */

--- a/js/src/jsobj.cpp
+++ b/js/src/jsobj.cpp
@@ -987,16 +987,34 @@ js_DefineOwnProperty(JSContext *cx, Hand
 
     bool rval;
     if (!DefineProperty(cx, obj, id, *desc, true, &rval))
         return false;
     *bp = !!rval;
     return true;
 }
 
+JSBool
+js_DefineOwnProperty(JSContext *cx, HandleObject obj, HandleId id,
+                     const PropertyDescriptor &descriptor, JSBool *bp)
+{
+    AutoPropDescArrayRooter descs(cx);
+    PropDesc *desc = descs.append();
+    if (!desc)
+        return false;
+
+    desc->initFromPropertyDescriptor(descriptor);
+
+    bool rval;
+    if (!DefineProperty(cx, obj, id, *desc, true, &rval))
+        return false;
+    *bp = !!rval;
+    return true;
+}
+
 
 bool
 js::ReadPropertyDescriptors(JSContext *cx, HandleObject props, bool checkAccessors,
                             AutoIdVector *ids, AutoPropDescArrayRooter *descs)
 {
     if (!GetPropertyNames(cx, props, JSITER_OWNONLY, ids))
         return false;
 

--- a/js/src/jsobj.h
+++ b/js/src/jsobj.h
@@ -1151,16 +1151,20 @@ extern js::RawShape
 js_AddNativeProperty(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                      JSPropertyOp getter, JSStrictPropertyOp setter, uint32_t slot,
                      unsigned attrs, unsigned flags, int shortid);
 
 extern JSBool
 js_DefineOwnProperty(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                      const JS::Value &descriptor, JSBool *bp);
 
+extern JSBool
+js_DefineOwnProperty(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
+                     const js::PropertyDescriptor &descriptor, JSBool *bp);
+
 namespace js {
 
 /*
  * The NewObjectKind allows an allocation site to specify the type properties
  * and lifetime requirements that must be fixed at allocation time.
  */
 enum NewObjectKind {
     /* This is the default. Most objects are generic. */