Suppress leak in AudioOutputController.

tools/valgrind/memcheck/suppressions.txt

Index: tools/valgrind/memcheck/suppressions.txt
diff --git a/tools/valgrind/memcheck/suppressions.txt b/tools/valgrind/memcheck/suppressions.txt
index d177ff1d19f02e05a3a7cb9e0571945a33df289f..4f6d439e85e0a97cf1876ff7f0140169f604bbe1 100644
--- a/tools/valgrind/memcheck/suppressions.txt
+++ b/tools/valgrind/memcheck/suppressions.txt
@@ -5767,6 +5767,18 @@
    fun:_ZN3ash5Shell14CreateInstanceEPNS_13ShellDelegateE
    fun:_ZN30ChromeBrowserMainExtraPartsAsh14PreProfileInitEv
 }
+{
+   bug_120146
+   Memcheck:Leak
+   fun:_Znw*
+   fun:_ZN4base8internal20PostTaskAndReplyImpl16PostTaskAndReplyERKN15tracked_objects8LocationERKNS_8CallbackIFvvEEESA_
+   fun:_ZN4base10TaskRunner16PostTaskAndReplyERKN15tracked_objects8LocationERKNS_8CallbackIFvvEEES9_
+   fun:_ZN5media21AudioOutputController5CloseERKN4base8CallbackIFvvEEE
+   fun:_ZN17AudioRendererHost20CloseAndDeleteStreamEPNS_10AudioEntryE
+   fun:_ZN17AudioRendererHost13DeleteEntriesEv
+   fun:_ZN17AudioRendererHost16OnChannelClosingEv
+   fun:_ZN3IPC12ChannelProxy7Context15OnChannelClosedEv
+}
 
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