[Not for review] record detailed time breakdown of SW related requests.

third_party/WebKit/Source/platform/network/ResourceResponse.h

Index: third_party/WebKit/Source/platform/network/ResourceResponse.h
diff --git a/third_party/WebKit/Source/platform/network/ResourceResponse.h b/third_party/WebKit/Source/platform/network/ResourceResponse.h
index f985e97898df15541428e9b762c01499e011a260..07ed74b2f39473b3a1e05063abc4e811df5a74c9 100644
--- a/third_party/WebKit/Source/platform/network/ResourceResponse.h
+++ b/third_party/WebKit/Source/platform/network/ResourceResponse.h
@@ -340,6 +340,10 @@ class PLATFORM_EXPORT ResourceResponse final {
 
   int64_t responseTime() const { return m_responseTime; }
   void setResponseTime(int64_t responseTime) { m_responseTime = responseTime; }
+  int64_t responseStart() const { return m_responseStart; }
+  void setResponseStart(int64_t responseStart) {
+    m_responseStart = responseStart;
+  }
 
   const AtomicString& remoteIPAddress() const { return m_remoteIPAddress; }
   void setRemoteIPAddress(const AtomicString& value) {
@@ -485,6 +489,7 @@ class PLATFORM_EXPORT ResourceResponse final {
   // The time at which the response headers were received.  For cached
   // responses, this time could be "far" in the past.
   int64_t m_responseTime;
+  int64_t m_responseStart;
 
   // Remote IP address of the socket which fetched this resource.
   AtomicString m_remoteIPAddress;
@@ -561,6 +566,7 @@ struct CrossThreadResourceResponseData {
   Vector<KURL> m_urlListViaServiceWorker;
   String m_cacheStorageCacheName;
   int64_t m_responseTime;
+  int64_t m_responseStart;
   String m_remoteIPAddress;
   unsigned short m_remotePort;
   long long m_encodedDataLength;