Fix NetLog thread safety issue

net/base/multi_threaded_cert_verifier.cc

Index: net/base/multi_threaded_cert_verifier.cc
===================================================================
--- net/base/multi_threaded_cert_verifier.cc	(revision 141669)
+++ net/base/multi_threaded_cert_verifier.cc	(working copy)
@@ -152,7 +152,7 @@
 
   // Returns the certificate being verified. May only be called /before/
   // Start() is called.
-  X509Certificate* certificate() const { return cert_; }
+  scoped_refptr<const X509Certificate> certificate() const { return cert_; }
 
   bool Start() {
     DCHECK_EQ(MessageLoop::current(), origin_loop_);
@@ -265,8 +265,7 @@
         net_log_(net_log) {
     net_log_.BeginEvent(
         NetLog::TYPE_CERT_VERIFIER_JOB,
-        base::Bind(&NetLogX509CertificateCallback,
-                   base::Unretained(worker_->certificate())));

[Ryan Sleevi, 2012/06/12 20:22:09]

This was safe as-is. Start() has not yet been called on |worker| (line 389), and
remains valid until HandleResult is called (line 201/205).

A temporary scoped_refptr<> would be created, since it's implicitly
constructable, so the change on 155 isn't necessary (and avoids one extra
AddRef/Release cycle)

+        CreateNetLogX509CertificateCallback(worker_->certificate()));
   }
 
   ~CertVerifierJob() {