diff --git a/js/xpconnect/src/XPCCallContext.cpp b/js/xpconnect/src/XPCCallContext.cpp
index a52577ba5ec..01b0394d908 100644
--- a/js/xpconnect/src/XPCCallContext.cpp
+++ b/js/xpconnect/src/XPCCallContext.cpp
@@ -60,6 +60,8 @@ XPCCallContext::XPCCallContext(XPCContext::LangType callerLanguage,
          nullptr, nullptr);
 }
 
+#define IS_TEAROFF_CLASS(clazz) ((clazz) == &XPC_WN_Tearoff_JSClass)
+
 void
 XPCCallContext::Init(XPCContext::LangType callerLanguage,
                      JSBool callBeginRequest,
@@ -144,10 +146,10 @@ XPCCallContext::Init(XPCContext::LangType callerLanguage,
 
     mTearOff = nullptr;
     if (wrapperInitOptions == INIT_SHOULD_LOOKUP_WRAPPER) {
-
         // If the object is a security wrapper, GetWrappedNativeOfJSObject can't
         // handle it. Do special handling here to make cross-origin Xrays work.
-        if (WrapperFactory::IsSecurityWrapper(obj)) {
+        JSObject *unwrapped = js::UnwrapObjectChecked(obj, /* stopAtOuter = */ false);
+        if (!unwrapped) {
             mWrapper = UnwrapThisIfAllowed(obj, funobj, argc);
             if (!mWrapper) {
                 JS_ReportError(mJSContext, "Permission denied to call method on |this|");
@@ -155,10 +157,16 @@ XPCCallContext::Init(XPCContext::LangType callerLanguage,
                 return;
             }
         } else {
-            mWrapper = XPCWrappedNative::GetWrappedNativeOfJSObject(mJSContext,
-                                                                    obj, funobj,
-                                                                    &mFlattenedJSObject,
-                                                                    &mTearOff);
+            js::Class *clasp = js::GetObjectClass(unwrapped);
+            if (IS_WRAPPER_CLASS(clasp)) {
+                if (IS_SLIM_WRAPPER_OBJECT(unwrapped))
+                    mFlattenedJSObject = unwrapped;
+                else
+                    mWrapper = XPCWrappedNative::Get(unwrapped);
+            } else if (IS_TEAROFF_CLASS(clasp)) {
+                mTearOff = (XPCWrappedNativeTearOff*)js::GetObjectPrivate(unwrapped);
+                mWrapper = XPCWrappedNative::Get(js::GetObjectParent(unwrapped));
+            }
         }
         if (mWrapper) {
             mFlattenedJSObject = mWrapper->GetFlatJSObject();
diff --git a/js/xpconnect/src/XPCWrappedNative.cpp b/js/xpconnect/src/XPCWrappedNative.cpp
index df068face00..5122f016a9b 100644
--- a/js/xpconnect/src/XPCWrappedNative.cpp
+++ b/js/xpconnect/src/XPCWrappedNative.cpp
@@ -1751,48 +1751,6 @@ XPCWrappedNative::RescueOrphans(XPCCallContext& ccx)
     return ::RescueOrphans(ccx, mFlatJSObject);
 }
 
-#define IS_TEAROFF_CLASS(clazz)                                               \
-          ((clazz) == &XPC_WN_Tearoff_JSClass)
-
-// static
-XPCWrappedNative*
-XPCWrappedNative::GetWrappedNativeOfJSObject(JSContext* cx,
-                                             JSObject* obj,
-                                             JSObject* funobj,
-                                             JSObject** pobj2,
-                                             XPCWrappedNativeTearOff** pTearOff)
-{
-    NS_PRECONDITION(obj, "bad param");
-
-    // fubobj must be null if called without cx.
-    NS_PRECONDITION(cx || !funobj, "bad param");
-
-    // *pTeaorOff must be null if pTearOff is given
-    NS_PRECONDITION(!pTearOff || !*pTearOff, "bad param");
-    if (pobj2)
-        *pobj2 = nullptr;
-
-    obj = js::UnwrapObjectChecked(obj, /* stopAtOuter = */ false);
-    if (!obj)
-        return nullptr;
-    js::Class *clasp = js::GetObjectClass(obj);
-    if (IS_WRAPPER_CLASS(clasp)) {
-        if (IS_WN_WRAPPER_OBJECT(obj)) {
-            return (XPCWrappedNative*)js::GetObjectPrivate(obj);
-        } else {
-            MOZ_ASSERT(IS_SLIM_WRAPPER_OBJECT(obj));
-            if (pobj2)
-                *pobj2 = obj;
-            return nullptr;
-        }
-    } else if (IS_TEAROFF_CLASS(clasp)) {
-        if (pTearOff)
-            *pTearOff = (XPCWrappedNativeTearOff*)js::GetObjectPrivate(obj);
-        return (XPCWrappedNative*)js::GetObjectPrivate(js::GetObjectParent(obj));
-    }
-    return nullptr;
-}
-
 JSBool
 XPCWrappedNative::ExtendSet(XPCCallContext& ccx, XPCNativeInterface* aInterface)
 {
diff --git a/js/xpconnect/src/xpcprivate.h b/js/xpconnect/src/xpcprivate.h
index d36afa30279..bbcf5435706 100644
--- a/js/xpconnect/src/xpcprivate.h
+++ b/js/xpconnect/src/xpcprivate.h
@@ -2753,15 +2753,6 @@ public:
                 XPCNativeInterface* Interface,
                 XPCWrappedNative** wrapper);
 
-    // If pobj2 is not null and *pobj2 is not null after the call then *pobj2
-    // points to an object for which IS_SLIM_WRAPPER_OBJECT is true.
-    // cx is null when invoked from the marking phase of the GC. In this case
-    // fubobj must be null as well.
-    static XPCWrappedNative*
-    GetWrappedNativeOfJSObject(JSContext* cx, JSObject* obj,
-                               JSObject* funobj = nullptr,
-                               JSObject** pobj2 = nullptr,
-                               XPCWrappedNativeTearOff** pTearOff = nullptr);
     static XPCWrappedNative*
     GetAndMorphWrappedNativeOfJSObject(JSContext* cx, JSObject* obj)
     {