Bug 1972282 - Check for spoof English in xsl:sort. a=diannaS

Original Revision: https://phabricator.services.mozilla.com/D254784

Differential Revision: https://phabricator.services.mozilla.com/D258855

dom/xslt/xpath/txXPathNode.h

@@ -66,6 +66,8 @@ class txXPathNode {
   bool operator!=(const txXPathNode& aNode) const { return !(*this == aNode); }
   ~txXPathNode() { MOZ_COUNT_DTOR(txXPathNode); }
 
+  mozilla::dom::Document* OwnerDoc() const { return mNode->OwnerDoc(); }
+
  private:
   friend class txXPathNativeNode;
   friend class txXPathNodeUtils;

dom/xslt/xslt/txNodeSorter.cpp

@@ -13,11 +13,14 @@
 
 #include "mozilla/CheckedInt.h"
 #include "mozilla/UniquePtrExtensions.h"
+#include "nsRFPService.h"
 
 using mozilla::CheckedUint32;
 using mozilla::MakeUnique;
 using mozilla::MakeUniqueFallible;
+using mozilla::RFPTarget;
 using mozilla::UniquePtr;
+using mozilla::nsRFPService;
 
 /*
  * Sorts Nodes as specified by the W3C XSLT 1.0 Recommendation
@@ -74,6 +77,10 @@ nsresult txNodeSorter::addSortElement(Expr* aSelectExpr, Expr* aLangExpr,
     if (aLangExpr) {
       rv = aLangExpr->evaluateToString(aContext, lang);
       NS_ENSURE_SUCCESS(rv, rv);
+    } else if (aContext->getContextNode()
+                   .OwnerDoc()
+                   ->ShouldResistFingerprinting(RFPTarget::JSLocale)) {
+      CopyUTF8toUTF16(nsRFPService::GetSpoofedJSLocale(), lang);
     }
 
     // Case-order