PerformanceMonitor: do not maintain a vector of frames in the monitor, single ExecutionContext memb…

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

Index: third_party/WebKit/Source/core/timing/Performance.h
diff --git a/third_party/WebKit/Source/core/timing/Performance.h b/third_party/WebKit/Source/core/timing/Performance.h
index 95bc1fb07652a56e43d13072d7bad3f19417b55d..339aaf8e084f8718842eed91c71f32c29adfd400 100644
--- a/third_party/WebKit/Source/core/timing/Performance.h
+++ b/third_party/WebKit/Source/core/timing/Performance.h
@@ -77,13 +77,15 @@ class CORE_EXPORT Performance final : public PerformanceBase,
   void frameDestroyed() override;
 
   static std::pair<String, DOMWindow*> sanitizedAttribution(
-      const HeapHashSet<Member<Frame>>& frames,
+      ExecutionContext*,
+      bool hasMultipleContexts,
       Frame* observerFrame);
 
   // PerformanceMonitor::Client implementation.
   void reportLongTask(double startTime,
                       double endTime,
-                      const HeapHashSet<Member<Frame>>& contextFrames) override;
+                      ExecutionContext* taskContext,
+                      bool hasMultipleContexts) override;
 
   mutable Member<PerformanceNavigation> m_navigation;
   mutable Member<PerformanceTiming> m_timing;