Broaden valgrind supression for known issue in zlib. This seems

tools/valgrind/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 # running overnight and removing outdated bugs/suppressions.
 #-----------------------------------------------------------------------
 
 # 1. third party stuff we have no control over
 {
    Uninitialized value in deflate
    Memcheck:Cond
-   fun:longest_match
-   fun:deflate_slow
+   ...
    fun:MOZ_Z_deflate
 }
 {
    gtk developers don't like cleaning up one-time leaks.  See http://mail.gnome.org/archives/gtk-devel-list/2004-April/msg00230.html
    Memcheck:Leak
    ...
    fun:gtk_init_check
 }
 {
    Fontconfig leak?
@@ skipping 588 matching lines @@
    fun:_ZN3gfx6Canvas13SizeStringIntERKSbIwSt11char_traitsIwESaIwEERKNS_4FontEPiSA_i
 }
 {
    # See bug 12539 and 12549
    bug_12539
    Memcheck:Leak
    ...
    fun:_ZN7WebCore11ImageSource18createFrameAtIndexEj
    fun:_ZNK11webkit_glue12ImageDecoder6DecodeEPKhj
 }