Add Net.CertVerifier_First_Job_Latency metric.

net/cert/multi_threaded_cert_verifier.cc

Index: net/cert/multi_threaded_cert_verifier.cc
diff --git a/net/cert/multi_threaded_cert_verifier.cc b/net/cert/multi_threaded_cert_verifier.cc
index 4b2f37fbc55b5295e771477c24bef172fd97c0fe..4fa29907a1697c2af97ee768226ddaac437a691b 100644
--- a/net/cert/multi_threaded_cert_verifier.cc
+++ b/net/cert/multi_threaded_cert_verifier.cc
@@ -320,9 +320,11 @@ class CertVerifierWorker {
 class CertVerifierJob {
  public:
   CertVerifierJob(CertVerifierWorker* worker,
+                  bool is_first_job,
                   const BoundNetLog& net_log)
       : start_time_(base::TimeTicks::Now()),
         worker_(worker),
+        is_first_job_(is_first_job),
         net_log_(net_log) {
     net_log_.BeginEvent(
         NetLog::TYPE_CERT_VERIFIER_JOB,
@@ -351,11 +353,19 @@ class CertVerifierJob {
       const MultiThreadedCertVerifier::CachedResult& verify_result) {
     worker_ = NULL;
     net_log_.EndEvent(NetLog::TYPE_CERT_VERIFIER_JOB);
+    base::TimeDelta latency = base::TimeTicks::Now() - start_time_;
     UMA_HISTOGRAM_CUSTOM_TIMES("Net.CertVerifier_Job_Latency",
-                               base::TimeTicks::Now() - start_time_,
+                               latency,
                                base::TimeDelta::FromMilliseconds(1),
                                base::TimeDelta::FromMinutes(10),
                                100);
+    if (is_first_job_) {
+      UMA_HISTOGRAM_CUSTOM_TIMES("Net.CertVerifier_First_Job_Latency",
+                                 latency,
+                                 base::TimeDelta::FromMilliseconds(1),
+                                 base::TimeDelta::FromMinutes(10),
+                                 100);
+    }
     PostAll(verify_result);
   }
 
@@ -385,6 +395,7 @@ class CertVerifierJob {
   const base::TimeTicks start_time_;
   std::vector<CertVerifierRequest*> requests_;
   CertVerifierWorker* worker_;
+  bool is_first_job_;
   const BoundNetLog net_log_;
 };
 
@@ -463,7 +474,7 @@ int MultiThreadedCertVerifier::Verify(X509Certificate* cert,
                                additional_trust_anchors,
                                this);
     job = new CertVerifierJob(
-        worker,
+        worker, requests_ == 1,
         BoundNetLog::Make(net_log.net_log(), NetLog::SOURCE_CERT_VERIFIER_JOB));
     if (!worker->Start()) {
       delete job;