Enable ServerTiming support

third_party/WebKit/Source/core/loader/DocumentLoader.cpp

Index: third_party/WebKit/Source/core/loader/DocumentLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
index 74025934ae868e7ed81e4722e04c809fc9f06e4a..900d0eb8f74ae503212581975d1941a9a26058e6 100644
--- a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
@@ -61,6 +61,8 @@
 #include "core/page/FrameTree.h"
 #include "core/page/Page.h"
 #include "core/probe/CoreProbes.h"
+#include "core/timing/DOMWindowPerformance.h"
+#include "core/timing/Performance.h"
 #include "platform/HTTPNames.h"
 #include "platform/UserGestureIndicator.h"
 #include "platform/feature_policy/FeaturePolicy.h"
@@ -956,6 +958,13 @@ void DocumentLoader::didInstallNewDocument(Document* document) {
     document->parseAndSetReferrerPolicy(referrerPolicyHeader);
   }
 
+  if (RuntimeEnabledFeatures::serverTimingEnabled() &&
+      m_frame->document()->domWindow()) {
+    DOMWindowPerformance::performance(*(m_frame->document()->domWindow()))
+        ->addServerTiming(m_response,
+                          PerformanceBase::ShouldAddToBuffer::Always);
+  }
+
   localFrameClient().didCreateNewDocument();
 }