Add traces to HttpCache::Transaction to make it easier to follow URLRequests

net/cert/x509_certificate.cc

Index: net/cert/x509_certificate.cc
diff --git a/net/cert/x509_certificate.cc b/net/cert/x509_certificate.cc
index 48cc5b5c8c509943151747cb8da85120c64ee2d8..60718f2d50977c6016650ecac97980f14b46a927 100644
--- a/net/cert/x509_certificate.cc
+++ b/net/cert/x509_certificate.cc
@@ -25,6 +25,7 @@
 #include "base/strings/string_util.h"
 #include "base/synchronization/lock.h"
 #include "base/time/time.h"
+#include "base/trace_event/trace_event.h"
 #include "crypto/secure_hash.h"
 #include "net/base/registry_controlled_domains/registry_controlled_domain.h"
 #include "net/base/url_util.h"
@@ -235,6 +236,8 @@ scoped_refptr<X509Certificate> X509Certificate::CreateFromHandle(
 // static
 scoped_refptr<X509Certificate> X509Certificate::CreateFromDERCertChain(
     const std::vector<base::StringPiece>& der_certs) {
+  TRACE_EVENT0("net", "X509Certificate::CreateFromDERCertChain");

[caseq, 2016/10/20 21:23:31]

Is this intended to be a part of this CL?

[jkarlin, 2016/10/24 17:20:58]

Yes, simply because it's a very expensive operation that we need to track,
though I admit it doesn't fit with the rest.

+
   // TODO(cbentzel): Remove ScopedTracker below once crbug.com/424386 is fixed.
   tracked_objects::ScopedTracker tracking_profile(
       FROM_HERE_WITH_EXPLICIT_FUNCTION(