Add tsan suppression for gamepad unittest code

BUG=79050


Review URL: http://codereview.chromium.org/8637025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@111262 0039d316-1c4b-4281-b951-d872f2087c98

tools/valgrind/tsan/suppressions.txt

@@ -392,6 +392,14 @@
    fun:base::StatisticsRecorder::FindHistogram
    fun:base::*Histogram::FactoryGet
 }
+{
+  bug_79050 Test to detect read contention & benign race
+  ThreadSanitizer:Race
+  fun:Replace_memcpy
+  fun:memcpy
+  fun:::MockDataFetcher::GetGamepadData
+  fun:gamepad::Provider::DoPoll
+}
 
 # 3. Suppressions for real chromium bugs that are not yet fixed.
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