[Resource Timing] Expose redirect timing information

Source/core/page/PerformanceTiming.cpp

Index: Source/core/page/PerformanceTiming.cpp
diff --git a/Source/core/page/PerformanceTiming.cpp b/Source/core/page/PerformanceTiming.cpp
index fe2b1c04e3ada77cf5981e123aa8279ed7695854..e39b513f436c5798eef85501f4c669e77948c79e 100644
--- a/Source/core/page/PerformanceTiming.cpp
+++ b/Source/core/page/PerformanceTiming.cpp
@@ -213,7 +213,7 @@ unsigned long long PerformanceTiming::secureConnectionStart() const
 unsigned long long PerformanceTiming::requestStart() const
 {
     ResourceLoadTiming* timing = resourceLoadTiming();
-    if (!timing)
+    if (!timing || timing->sendStart < 0)
         return connectEnd();
 
     ASSERT(timing->sendStart >= 0);
@@ -223,7 +223,7 @@ unsigned long long PerformanceTiming::requestStart() const
 unsigned long long PerformanceTiming::responseStart() const
 {
     ResourceLoadTiming* timing = resourceLoadTiming();
-    if (!timing)
+    if (!timing || timing->receiveHeadersEnd < 0)
         return requestStart();
 
     // FIXME: Response start needs to be the time of the first received byte.