Widen NetworkInfoDictionary::set_icon suppression.

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 # running overnight and removing outdated bugs/suppressions.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 4412 matching lines @@
    fun:_ZN2v88internal12Deserializer9ReadChunkEPPNS0_6ObjectES4_iPh
    fun:_ZN2v88internal12Deserializer13VisitPointersEPPNS0_6ObjectES4_
 }
 {
    bug_99307
    Memcheck:Uninitialized
    fun:modp_b64_encode
    fun:_ZN4base12Base64EncodeERKNS_11StringPieceEPSs
    fun:_ZN11web_ui_util15GetImageDataUrlERK8SkBitmap
    fun:_ZN12_GLOBAL__N_121NetworkInfoDictionary8set_iconERK8SkBitmap
-   fun:_ZN12_GLOBAL__N_121NetworkInfoDictionaryC1EPKN8chromeos7NetworkE*
 }
 {
    bug_99308
    Memcheck:Leak
    fun:malloc
    fun:_ZL9toCStringRK9_NPString
    fun:_ZL15testPostURLFileP12PluginObjectPK10_NPVariantjPS1_
    fun:_ZL12pluginInvokeP8NPObjectPvPK10_NPVariantjPS2_
    fun:_ZN7WebCoreL18npObjectInvokeImplERKN2v89ArgumentsENS_18InvokeFunctionTypeE
 }
@@ skipping 804 matching lines @@
    obj:/lib/libselinux.so.1
    obj:/lib/libselinux.so.1
 }
 {
    bug_todo_grep
    Memcheck:Leak
    fun:malloc
    obj:/bin/grep
    obj:/bin/grep
 }