Update a couple of suppression rules.

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 # running overnight and removing outdated bugs/suppressions.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 2591 matching lines @@
    fun:_ZN3gfx20GetGLCoreProcAddressEPKc
    fun:_ZN3gfx22InitializeGLBindingsGLEv
    fun:_ZN3gfx20InitializeGLBindingsENS_16GLImplementationE
    fun:_ZN3gfx9GLSurface16InitializeOneOffEv
 }
 {
    bug_68069_b
    Memcheck:Leak
    fun:malloc
    fun:XextCreateExtension
-   obj:*
-   obj:*
+   ...
    fun:_ZN3gfx12GLSurfaceGLX16InitializeOneOffEv
    fun:_ZN3gfx9GLSurface24InitializeOneOffInternalEv
    fun:_ZN3gfx9GLSurface16InitializeOneOffEv
 }
 {
    bug_68553
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN3net25DiskCacheBasedSSLHostInfoC1ERKSsRKNS_9SSLConfigEPNS_12CertVerifierEPNS_9HttpCacheE
    fun:_ZN3net9HttpCache25SSLHostInfoFactoryAdaptor10GetForHostERKSsRKNS_9SSLConfigE
@@ skipping 3235 matching lines @@
    obj:/lib/libselinux.so.1
 }
 {
    bug_todo_grep
    Memcheck:Leak
    fun:malloc
    obj:/bin/grep
    obj:/bin/grep
 }