tsan: Suppress a race

tools/valgrind/tsan/suppressions.txt

 # There are a few 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 # running overnight and removing outdated bugs/suppressions.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 956 matching lines @@
    ...
    fun:testing::internal::UntypedFunctionMockerBase::UntypedInvokeWith
    fun:testing::internal::FunctionMockerBase::InvokeWith
    fun:testing::internal::FunctionMocker::Invoke
    fun:browser_sync::NewNonFrontendDataTypeControllerMock::RecordUnrecoverableError
    fun:browser_sync::::NewNonFrontendDataTypeControllerFake::RecordUnrecoverableError
    fun:browser_sync::NonFrontendDataTypeController::StartFailed
    fun:browser_sync::NewNonFrontendDataTypeController::StartAssociationWithSharedChangeProcessor
    fun:base::internal::RunnableAdapter::Run
 }
+{
+  bug_144894
+  ThreadSanitizer:Race
+  fun:av_parser_close
+  fun:avcodec_open2
+  fun:avformat_find_stream_info
+  fun:media::FFmpegConfigHelper::SetupStreamConfigs
+  fun:media::FFmpegConfigHelper::Parse
+  fun:media::WebMStreamParser::ParseInfoAndTracks
+  fun:media::WebMStreamParser::Parse
+  fun:media::ChunkDemuxer::AppendData
+  fun:media::MockMediaSource::AppendAtTime
+  fun:media::PipelineIntegrationTest_MediaSource_ConfigChange_WebM_Test::TestBody
+}