Valgrind: Remove the suppression for bug 91157 since the method has been removed.

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 # running overnight and removing outdated bugs/suppressions.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 5102 matching lines @@
 {
    bug_90973
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN3net9HttpCache11CreateEntryERKSsPPNS0_11ActiveEntryEPNS0_11TransactionE
    fun:_ZN3net9HttpCache11Transaction13DoCreateEntryEv
    fun:_ZN3net9HttpCache11Transaction6DoLoopEi
    fun:_ZN3net9HttpCache11Transaction12OnIOCompleteEi
 }
 {
-   bug_91157
-   Memcheck:Leak
-   fun:_Znw*
-   fun:_ZN15DownloadManager24OnPathExistenceAvailableEiRK17DownloadStateInfo
-   fun:_Z16DispatchToMethodI15DownloadManagerMS0_FviRK17DownloadStateInfoEiS1_EvPT_T0_RK6Tuple2IT1_T2_E
-   fun:_ZN14RunnableMethodI15DownloadManagerMS0_FviRK17DownloadStateInfoE6Tuple2IiS1_EE3RunEv
-   fun:_ZN4base6subtle18TaskClosureAdapter3RunEv
-   fun:_ZN4base8internal8Invoker1ILb0ENS0_15InvokerStorage1IMNS_6subtle18TaskClosureAdapterEFvvEPS4_EES6_E8DoInvokeEPNS0_18InvokerStorageBaseE
-   fun:_ZNK4base8CallbackIFvvEE3RunEv
-   fun:_ZN11MessageLoop7RunTaskERKNS_11PendingTaskE
-   fun:_ZN11MessageLoop21DeferOrRunPendingTaskERKNS_11PendingTaskE
-   fun:_ZN11MessageLoop6DoWorkEv
-}
-{
    bug_91179
    Memcheck:Addr1
    fun:_ZN8chromeos21ParallelAuthenticator7ResolveEv
 }
 {
    bug_91199
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN19URLRequestChromeJob15GetResponseInfoEPN3net16HttpResponseInfoE
    fun:_ZN3net13URLRequestJob21NotifyHeadersCompleteEv
@@ skipping 310 matching lines @@
 }
 {
    bug_todo_getdelim2
    Memcheck:Leak
    fun:malloc
    fun:getdelim
    obj:/lib/libselinux.so.1
    obj:/lib/libselinux.so.1
    obj:/lib/libselinux.so.1
 }