Auto merge of #23812 - tdelacour:ISSUE-21257, r=jdm

ISSUE-21257: set redirectEnd on PerformanceResourceTiming

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Added the appropriate attribute and setters. Included a Timer struct with a `Drop` function to set this value to zero in error cases. Set the value to `responseEnd` on success. Eliminated tests that now pass.

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- [X] These changes fix #21257 (GitHub issue number if applicable)

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components/script/dom/webidls/PerformanceResourceTiming.webidl

@@ -13,7 +13,7 @@ interface PerformanceResourceTiming : PerformanceEntry {
     readonly attribute DOMString           nextHopProtocol;
     // readonly attribute DOMHighResTimeStamp workerStart;
     readonly attribute DOMHighResTimeStamp redirectStart;
-    // readonly attribute DOMHighResTimeStamp redirectEnd;
+    readonly attribute DOMHighResTimeStamp redirectEnd;
     readonly attribute DOMHighResTimeStamp fetchStart;
     readonly attribute DOMHighResTimeStamp domainLookupStart;
     // readonly attribute DOMHighResTimeStamp domainLookupEnd;