Update suppression caused by r42700

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 # running overnight and removing outdated bugs/suppressions.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 1880 matching lines @@
    fun:zipCloseFileInZipRaw
    fun:zipCloseFileInZip
    fun:_Z13AddEntryToZipPvRK8FilePathS2_
 }
 {
    bug_30704a
    Memcheck:Value4
    fun:crc32
    ...
    fun:png_write_row
+   fun:_ZN3gfx51_GLOBAL__N_gfx_codec_png_codec.cc_00000000_*
    fun:_ZN3gfx8PNGCodec6EncodeEPKhNS0_11ColorFormatEiiibPSt6vectorIhSaIhEE
    fun:_ZN3gfx8PNGCodec18EncodeBGRASkBitmapERK8SkBitmapbPSt6vectorIhSaIhEE
 }
 {
    bug_30704b
    Memcheck:Value8
    fun:crc32
    ...
    fun:png_write_row
+   fun:_ZN3gfx51_GLOBAL__N_gfx_codec_png_codec.cc_00000000_*
    fun:_ZN3gfx8PNGCodec6EncodeEPKhNS0_11ColorFormatEiiibPSt6vectorIhSaIhEE
    fun:_ZN3gfx8PNGCodec18EncodeBGRASkBitmapERK8SkBitmapbPSt6vectorIhSaIhEE
 }
 {
    bug_30704c
    Memcheck:Param
    write(buf)
    ...
    fun:_ZN26SandboxedExtensionUnpacker17RewriteImageFilesEv
 }
@@ skipping 708 matching lines @@
    fun:_ZNSt4listI13scoped_refptrIN3net11SpdySessionEESaIS3_EE9_M_insertESt14_List_iteratorIS3_ERKS3_
    fun:_ZNSt4listI13scoped_refptrIN3net11SpdySessionEESaIS3_EE9push_backERKS3_
    fun:_ZN3net15SpdySessionPool3GetERKNS_12HostPortPairEPNS_18HttpNetworkSessionE
    fun:_ZN3net22SpdyNetworkTransaction16DoInitConnectionEv
    fun:_ZN3net22SpdyNetworkTransaction6DoLoopEi
    fun:_ZN3net22SpdyNetworkTransaction5StartEPKNS_15HttpRequestInfoEP14CallbackRunnerI6Tuple1IiEERKNS_11BoundNetLogE
    fun:_ZN3net11MakeRequestE13scoped_refptrINS_18HttpNetworkSessionEES0_INS_17OrderedSocketDataEERK4GURLRKSsiiPNS_16HttpResponseInfoE
    fun:_ZN3net42SpdyNetworkTransactionTest_ServerPush_Test8TestBodyEv
    ...
 }