Report nav timing 2 instance as soon as it's requested.

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 882a008281bcf5d309b7c80a0247cbfeb22701ff..20b163ac5a7cf932dccb961f650d695f9ac43d4d 100644
--- a/third_party/WebKit/Source/core/timing/PerformanceBase.h
+++ b/third_party/WebKit/Source/core/timing/PerformanceBase.h
@@ -88,7 +88,7 @@ class CORE_EXPORT PerformanceBase : public EventTargetWithInlineData {
 
   double timeOrigin() const { return m_timeOrigin; }
 
-  PerformanceEntryVector getEntries() const;
+  PerformanceEntryVector getEntries();
   PerformanceEntryVector getEntriesByType(const String& entryType);
   PerformanceEntryVector getEntriesByName(const String& name,
                                           const String& entryType);
@@ -112,7 +112,7 @@ class CORE_EXPORT PerformanceBase : public EventTargetWithInlineData {
 
   void addResourceTiming(const ResourceTimingInfo&);
 
-  void addNavigationTiming(LocalFrame*);
+  void notifyNavigationTimingToObservers();
 
   void addFirstPaintTiming(double startTime);
 
@@ -133,18 +133,14 @@ class CORE_EXPORT PerformanceBase : public EventTargetWithInlineData {
   void activateObserver(PerformanceObserver&);
   void resumeSuspendedObservers();
 
-  DECLARE_VIRTUAL_TRACE();
-
- private:
-  static PerformanceNavigationTiming::NavigationType getNavigationType(
-      NavigationType,
-      const Document*);
-
   static bool allowsTimingRedirect(const Vector<ResourceResponse>&,
                                    const ResourceResponse&,
                                    const SecurityOrigin&,
                                    ExecutionContext*);
 
+  DECLARE_VIRTUAL_TRACE();
+
+ private:
   static bool passesTimingAllowCheck(const ResourceResponse&,
                                      const SecurityOrigin&,
                                      const AtomicString&,
@@ -155,6 +151,12 @@ class CORE_EXPORT PerformanceBase : public EventTargetWithInlineData {
  protected:
   explicit PerformanceBase(double timeOrigin, RefPtr<WebTaskRunner>);
 
+  // Expect Performance to override this method,
+  // WorkerPerformance doesn't have to override this.
+  virtual PerformanceNavigationTiming* createNavigationTimingInstance() {
+    return nullptr;
+  }
+
   bool isResourceTimingBufferFull();
   void addResourceTimingBuffer(PerformanceEntry&);