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

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

Index: third_party/WebKit/Source/core/timing/Performance.cpp
diff --git a/third_party/WebKit/Source/core/timing/Performance.cpp b/third_party/WebKit/Source/core/timing/Performance.cpp
index b5a7447cdce29c10697f4262a00d1ffec3e74041..9cd0a1fb39f5421ab20ae1f0a634f0eb6e5fded4 100644
--- a/third_party/WebKit/Source/core/timing/Performance.cpp
+++ b/third_party/WebKit/Source/core/timing/Performance.cpp
@@ -43,6 +43,7 @@
 #include "core/loader/DocumentLoader.h"
 #include "core/origin_trials/OriginTrials.h"
 #include "core/timing/PerformanceTiming.h"
+#include "platform/network/ResourceTimingInfo.h"
 
 static const double kLongTaskThreshold = 0.05;
 
@@ -140,6 +141,19 @@ PerformanceTiming* Performance::timing() const {
   return m_timing.get();
 }
 
+std::unique_ptr<ResourceTimingInfo> Performance::getNavigationTimingInfo()
+    const {
+  DCHECK(frame());
+  const DocumentLoader* documentLoader = frame()->loader().documentLoader();
+  DCHECK(documentLoader);
+  return documentLoader->getNavigationTimingInfo();
+}
+
+PerformanceNavigationTiming* Performance::getNavigationTimingInstance() {

[panicker, 2017/02/03 23:53:52]

createNavigationTimingInstance?

[sunjian, 2017/02/10 18:32:46]

Done.

+  return new PerformanceNavigationTiming(frame(), getNavigationTimingInfo(),
+                                         toTimeOrigin(frame()));
+}
+
 void Performance::updateLongTaskInstrumentation() {
   DCHECK(frame());
   if (!frame()->document() ||