Bug 42472: Spoof timezone in XSLT.

dom/xslt/xslt/txEXSLTFunctions.cpp

@@ -590,7 +590,14 @@ nsresult txEXSLTFunctionCall::evaluate(txIEvalContext* aContext,
       // http://exslt.org/date/functions/date-time/
 
       PRExplodedTime prtime;
-      PR_ExplodeTime(PR_Now(), PR_LocalTimeParameters, &prtime);
+      PR_ExplodeTime(PR_Now(),
+                     nsContentUtils::ShouldResistFingerprinting(
+                         "We are not allowed to access the document at this "
+                         "stage (we are given a txEarlyEvalContext context).",
+                         RFPTarget::JSDateTimeUTC)
+                         ? PR_GMTParameters
+                         : PR_LocalTimeParameters,
+                     &prtime);
 
       int32_t offset =
           (prtime.tm_params.tp_gmt_offset + prtime.tm_params.tp_dst_offset) /