Fix a leak in client_cert_resolver

tools/valgrind/memcheck/suppressions.txt

 # There are four kinds of suppressions in this file.
 # 1. third party stuff we have no control over
 #
 # 2. intentional unit test errors, or stuff that is somehow a false positive
 # in our own code, or stuff that is so trivial it's not worth fixing
 #
 # 3. Suppressions for real chromium bugs that are not yet fixed.
 # These should all be in chromium's bug tracking system (but a few aren't yet).
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
@@ skipping 5868 matching lines @@
    fun:_Znw*
    fun:_ZN9__gnu_cxx13new_allocatorIPN4base11PendingTaskEE8allocateEmPKv
    fun:_ZNSt11_Deque_baseIN4base11PendingTaskESaIS1_EE15_M_allocate_mapEm
    fun:_ZNSt5dequeIN4base11PendingTaskESaIS1_EE17_M_reallocate_mapEmb
    ...
    fun:_ZN4base8internal17IncomingTaskQueue15PostPendingTaskEPNS_11PendingTaskE
    fun:_ZN4base8internal17IncomingTaskQueue18AddToIncomingQueueERKN15tracked_objects8LocationERKNS_8CallbackIFvvEEENS_9TimeDeltaEb
    fun:_ZN4base11MessageLoop8PostTaskERKN15tracked_objects8LocationERKNS_8CallbackIFvvEEE
 }
 {
-   bug_272596
-   Memcheck:Leak
-   ...
-   fun:nssPKIObjectCollection_AddInstanceAsObject
-   fun:nssToken_TraverseCertificates
-   fun:NSSTrustDomain_TraverseCertificates
-   fun:PK11_ListCerts
-   fun:_ZN3net15NSSCertDatabase9ListCertsEPSt6vectorI13scoped_refptrINS_15X509CertificateEESaIS4_EE
-   fun:_ZN3net23NSSCertDatabaseChromeOS9ListCertsEPSt6vectorI13scoped_refptrINS_15X509CertificateEESaIS4_EE
-   fun:_ZN8chromeos12_GLOBAL__N_119LoadNSSCertificatesEPN3net15NSSCertDatabaseEPSt6vectorI13scoped_refptrINS1_15X509CertificateEESaIS7_EE
-}
-{
    bug_273398
    Memcheck:Leak
    ...
    fun:_ZN6Pickle6ResizeEm
    fun:_ZN6PickleC1Ev
    fun:_ZN7content14ZygoteHostImpl20GetTerminationStatusEibPi
    fun:_ZN7content20ChildProcessLauncher25GetChildTerminationStatusEbPi
 }
 {
    bug_274193
@@ skipping 465 matching lines @@
    fun:_ZN15google_breakpad16ExceptionHandler12HandleSignalEiP7siginfoPv
    fun:_ZN15google_breakpad16ExceptionHandler13SignalHandlerEiP7siginfoPv
 }
 {
    bug_333992
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN7content12_GLOBAL__N_123CreateWebFrameTestProxyEPNS_14RenderViewImplEi
    fun:_ZN7content15RenderFrameImpl6CreateEPNS_14RenderViewImplEi
 }