Enable ServerTiming support

third_party/WebKit/Source/core/timing/PerformanceBase.h

Index: third_party/WebKit/Source/core/timing/PerformanceBase.h
diff --git a/third_party/WebKit/Source/core/timing/PerformanceBase.h b/third_party/WebKit/Source/core/timing/PerformanceBase.h
index cd75b5dd400a7d690d0686f6ba805f8805c61bc2..4913159574a30bc83e1e9f8ec3166782d79b110c 100644
--- a/third_party/WebKit/Source/core/timing/PerformanceBase.h
+++ b/third_party/WebKit/Source/core/timing/PerformanceBase.h
@@ -111,6 +111,12 @@ class CORE_EXPORT PerformanceBase : public EventTargetWithInlineData {
 
   void AddResourceTiming(const ResourceTimingInfo&);
 
+  enum class ShouldAddToBuffer {
+    Always,
+    Never,
+  };
+  void AddServerTiming(const ResourceResponse&, ShouldAddToBuffer);
+
   void NotifyNavigationTimingToObservers();
 
   void AddFirstPaintTiming(double start_time);
@@ -163,6 +169,7 @@ class CORE_EXPORT PerformanceBase : public EventTargetWithInlineData {
   void AddFrameTimingBuffer(PerformanceEntry&);
 
   void NotifyObserversOfEntry(PerformanceEntry&);
+  void NotifyObserversOfEntries(PerformanceEntryVector&);
   bool HasObserverFor(PerformanceEntry::EntryType) const;
 
   void DeliverObservationsTimerFired(TimerBase*);
@@ -171,6 +178,7 @@ class CORE_EXPORT PerformanceBase : public EventTargetWithInlineData {
   unsigned frame_timing_buffer_size_;
   PerformanceEntryVector resource_timing_buffer_;
   unsigned resource_timing_buffer_size_;
+  PerformanceEntryVector server_timing_buffer_;
   Member<PerformanceEntry> navigation_timing_;
   Member<UserTiming> user_timing_;