--- a/dom/base/test/TestGetURL.cpp
+++ b/dom/base/test/TestGetURL.cpp
@@ -39,17 +39,17 @@ nsresult TestGetURL(const nsCString& aUR
   nsCOMPtr<nsIScriptSecurityManager> secman =
     do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
   TEST_ENSURE_SUCCESS(rv, "Couldn't get script security manager!");
 
   nsCOMPtr<nsIPrincipal> systemPrincipal;
   rv = secman->GetSystemPrincipal(getter_AddRefs(systemPrincipal));
   TEST_ENSURE_SUCCESS(rv, "Couldn't get system principal!");
 
-  rv = xhr->Init(systemPrincipal, nullptr, nullptr, nullptr, nullptr);
+  rv = xhr->Init(systemPrincipal, nullptr, nullptr, nullptr);
   TEST_ENSURE_SUCCESS(rv, "Couldn't initialize the XHR!");
 
   rv = xhr->Open(getString, aURL, false, empty, empty);
   TEST_ENSURE_SUCCESS(rv, "OpenRequest failed!");
 
   rv = xhr->Send(nullptr);
   TEST_ENSURE_SUCCESS(rv, "Send failed!");
 

--- a/dom/base/test/TestNativeXMLHttpRequest.cpp
+++ b/dom/base/test/TestNativeXMLHttpRequest.cpp
@@ -49,17 +49,17 @@ nsresult TestNativeXMLHttpRequest()
   nsCOMPtr<nsIScriptSecurityManager> secman =
     do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
   TEST_ENSURE_SUCCESS(rv, "Couldn't get script security manager!");
 
   nsCOMPtr<nsIPrincipal> systemPrincipal;
   rv = secman->GetSystemPrincipal(getter_AddRefs(systemPrincipal));
   TEST_ENSURE_SUCCESS(rv, "Couldn't get system principal!");
 
-  rv = xhr->Init(systemPrincipal, nullptr, nullptr, nullptr, nullptr);
+  rv = xhr->Init(systemPrincipal, nullptr, nullptr, nullptr);
   TEST_ENSURE_SUCCESS(rv, "Couldn't initialize the XHR!");
 
   rv = xhr->Open(getString, testURL, false, empty, empty);
   TEST_ENSURE_SUCCESS(rv, "Open failed!");
 
   rv = xhr->Send(nullptr);
   TEST_ENSURE_SUCCESS(rv, "Send failed!");
 

--- a/dom/xhr/XMLHttpRequestMainThread.cpp
+++ b/dom/xhr/XMLHttpRequestMainThread.cpp
@@ -228,17 +228,16 @@ XMLHttpRequestMainThread::Init()
   return NS_OK;
 }
 
 /**
  * This Init method should only be called by C++ consumers.
  */
 NS_IMETHODIMP
 XMLHttpRequestMainThread::Init(nsIPrincipal* aPrincipal,
-                               nsIScriptContext* aScriptContext,
                                nsIGlobalObject* aGlobalObject,
                                nsIURI* aBaseURI,
                                nsILoadGroup* aLoadGroup)
 {
   NS_ENSURE_ARG_POINTER(aPrincipal);
   Construct(aPrincipal, aGlobalObject, aBaseURI, aLoadGroup);
   return NS_OK;
 }

--- a/dom/xhr/XMLHttpRequestMainThread.h
+++ b/dom/xhr/XMLHttpRequestMainThread.h
@@ -546,17 +546,16 @@ public:
   // received data since the last "progress" event. Also dispatches
   // "uploadprogress" as needed.
   void MaybeDispatchProgressEvents(bool aFinalProgress);
 
   // This is called by the factory constructor.
   nsresult Init();
 
   nsresult init(nsIPrincipal* principal,
-                nsIScriptContext* scriptContext,
                 nsPIDOMWindowInner* globalObject,
                 nsIURI* baseURI);
 
   void SetRequestObserver(nsIRequestObserver* aObserver);
 
   NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS_INHERITED(XMLHttpRequestMainThread,
                                                                    XMLHttpRequest)
   bool AllowUploadProgress();

--- a/dom/xhr/nsIXMLHttpRequest.idl
+++ b/dom/xhr/nsIXMLHttpRequest.idl
@@ -274,30 +274,27 @@ interface nsIXMLHttpRequest : nsISupport
   attribute boolean withCredentials;
 
   /**
    * Initialize the object for use from C++ code with the principal, script
    * context, and owner window that should be used.
    *
    * @param principal The principal to use for the request. This must not be
    *                  null.
-   * @param scriptContext The script context to use for the request. May be
-   *                      null.
    * @param globalObject The associated global for the request. Can be the
    *                     outer window, a sandbox, or a backstage pass.
    *                     May be null, but then the request cannot create a
    *                     document.
    * @param baseURI The base URI to use when resolving relative URIs. May be
    *                null.
    * @param loadGroup An optional load group to use when performing the request.
    *                  This will be used even if the global has a window with a
    *                  load group.
    */
   [noscript] void init(in nsIPrincipal principal,
-                       in nsIScriptContext scriptContext,
                        in nsIGlobalObject globalObject,
                        in nsIURI baseURI,
                        [optional] in nsILoadGroup loadGroup);
 
   /**
    * Upload process can be tracked by adding event listener to |upload|.
    */
   readonly attribute nsIXMLHttpRequestUpload upload;

--- a/dom/xul/templates/nsXULTemplateQueryProcessorXML.cpp
+++ b/dom/xul/templates/nsXULTemplateQueryProcessorXML.cpp
@@ -152,26 +152,21 @@ nsXULTemplateQueryProcessorXML::GetDatas
 
     nsIPrincipal *docPrincipal = doc->NodePrincipal();
 
     bool hasHadScriptObject = true;
     nsIScriptGlobalObject* scriptObject =
       doc->GetScriptHandlingObject(hasHadScriptObject);
     NS_ENSURE_STATE(scriptObject);
 
-    nsIScriptContext *context = scriptObject->GetContext();
-    NS_ENSURE_TRUE(context, NS_OK);
-
     nsCOMPtr<nsIXMLHttpRequest> req =
         do_CreateInstance(NS_XMLHTTPREQUEST_CONTRACTID, &rv);
     NS_ENSURE_SUCCESS(rv, rv);
 
-    rv = req->Init(docPrincipal, context,
-                   scriptObject ? scriptObject : doc->GetScopeObject(),
-                   nullptr, nullptr);
+    rv = req->Init(docPrincipal, scriptObject, nullptr, nullptr);
     NS_ENSURE_SUCCESS(rv, rv);
 
     rv = req->Open(NS_LITERAL_CSTRING("GET"), uriStr, true,
                    EmptyString(), EmptyString());
     NS_ENSURE_SUCCESS(rv, rv);
 
     nsCOMPtr<EventTarget> target(do_QueryInterface(req));
     rv = target->AddEventListener(NS_LITERAL_STRING("load"), this, false);