Suppression for issue FFmpegVideoDecoder::Flush

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 # running overnight and removing outdated bugs/suppressions.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 725 matching lines @@
   fun:ResourceDispatcherHost::StartReading
   fun:ResourceDispatcherHost::ResumeRequest
   fun:base::internal::RunnableAdapter::Run
 }
 {
   bug_108411
   ThreadSanitizer:Race
   ...
   fun:pa_rtpoll_run
 }
+{
+  bug_112200
+  ThreadSanitizer:Race
+  fun:park_frame_worker_threads
+  fun:ff_thread_flush
+  fun:avcodec_flush_buffers
+  fun:avcodec_flush_buffers
+  fun:media::FFmpegVideoDecoder::Flush
+  fun:base::internal::RunnableAdapter::Run
+}