Suppress memcheck errors on linux bot.

tools/valgrind-webrtc/memcheck/suppressions.txt

Index: tools/valgrind-webrtc/memcheck/suppressions.txt
diff --git a/tools/valgrind-webrtc/memcheck/suppressions.txt b/tools/valgrind-webrtc/memcheck/suppressions.txt
index 28ab2766d015534deb41a9161f0aa457299a9396..51d08a6d65a5005e2df2027381d17ed2739d9449 100644
--- a/tools/valgrind-webrtc/memcheck/suppressions.txt
+++ b/tools/valgrind-webrtc/memcheck/suppressions.txt
@@ -263,6 +263,17 @@
    fun:WebRtcNetEQ_GetSpeechOutputType
    ...
 }
+{
+   vfprintf

[kjellander_webrtc, 2016/08/26 08:04:08]

Yes, this suppression matches the two listed in
https://uberchromegw.corp.google.com/i/tryserver.webrtc/builders/linux_memche...

+   Memcheck:Uninitialized
+   ...

[kjellander_webrtc, 2016/08/26 08:09:01]

Actually, add
   fun:vfprintf
   fun:vsnprintf
   fun:snprintf
before the ... wildcard will make the suppression more precise.

+   fun:_ZNK7testing8internal18FunctionMockerBaseIFbRKN6webrtc4rtcp17TransportFeedbackEEE32UntypedDescribeUninterestingCallEPKvPSo
+   fun:_ZN7testing8internal25UntypedFunctionMockerBase17UntypedInvokeWithEPKv
+   fun:_ZN6webrtc11MockRtpRtcp18SendFeedbackPacketERKNS_4rtcp17TransportFeedbackE
+   fun:_ZN6webrtc12PacketRouter12SendFeedbackEPNS_4rtcp17TransportFeedbackE
+   fun:_ZN6webrtc34PacketRouterTest_SendFeedback_Test8TestBodyEv
+}
+
 
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