Update valgrind suppressions for mac_util::SetFileBackupExclusion leaks.

tools/valgrind/memcheck/suppressions.txt

 # There are three 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 # running overnight and removing outdated bugs/suppressions.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 1674 matching lines @@
    fun:AEProcessAppleEvent
    fun:_DPSNextEvent
    fun:-[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:]
    fun:-[NSApplication run]
    fun:_ZN4base24MessagePumpNSApplication5DoRunEPNS_11MessagePump8DelegateE
    fun:_ZN4base24MessagePumpCFRunLoopBase3RunEPNS_11MessagePump8DelegateE
    fun:_ZN11MessageLoop11RunInternalEv
    fun:_ZN11MessageLoop10RunHandlerEv
 }
 {
-   bug_28072
-   Memcheck:Leak
-   fun:malloc_zone_malloc
-   fun:_CFRuntimeCreateInstance
-   fun:__CFStringCreateImmutableFunnel3
-   fun:CFStringCreateWithBytes
-   fun:__CFBinaryPlistCreateObject2
-   fun:__CFBinaryPlistCreateObject2
-   fun:__CFBinaryPlistCreateObject2
-   fun:__CFTryParseBinaryPlist
-   fun:_CFPropertyListCreateFromXMLData
-   fun:CFPropertyListCreateFromStream
-   fun:+[CFXPreferencesPropertyListSource createPlistFromFile:statInfo:]
-   fun:-[CFXPreferencesPropertyListSource synchronize]
-   fun:CFPreferencesSynchronize
-   fun:_CSBackupSettingsExcludePath
-   fun:CSBackupSetItemExcluded
-   fun:_ZN8mac_util22SetFileBackupExclusionERK8FilePathb
-   fun:_ZN7history15HistoryDatabase4InitERK8FilePathS3_
-   fun:_ZN7history14HistoryBackend8InitImplEv
-   fun:_ZN7history14HistoryBackend4InitEb
-   fun:_Z16DispatchToMethodIN7history14HistoryBackendEMS1_FvbEbEvPT_T0_RK6Tuple1IT1_E
-   fun:_ZN14RunnableMethodIN7history14HistoryBackendEMS1_FvbE6Tuple1IbEE3RunEv
-   fun:_ZN11MessageLoop7RunTaskEP4Task
-}
-{
    bug_28200
    Memcheck:Leak
    fun:malloc
    fun:malloc
    fun:_ZN3WTF10fastMallocEj
    fun:_ZN3WTF13FastAllocBasenwEj
    fun:_ZN7WebCore18MessagePortChannel6createEN3WTF10PassRefPtrINS_26PlatformMessagePortChannelEEE
    fun:_ZN6WebKit19WebSharedWorkerImpl7connectEPNS_21WebMessagePortChannelEPNS_15WebSharedWorker15ConnectListenerE
    fun:_ZN19WebSharedWorkerStub9OnConnectEii
 }
@@ skipping 159 matching lines @@
    fun:_ZN3net22FlipNetworkTransaction5StartEPKNS_15HttpRequestInfoEP14CallbackRunnerI6Tuple1IiEEPNS_7LoadLogE
 }
 {
    bug_29675
    Memcheck:Leak
    fun:_Znw*
    fun:_Z11BrowserMainRK18MainFunctionParams
    fun:ChromeMain
    fun:main
 }