Valgrind suppression: lead of WorkerThread in worker_pool_posix

tools/valgrind/memcheck/suppressions.txt

 # There are four 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 # running overnight and removing outdated bugs/suppressions.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 3121 matching lines @@
    fun:_ZN28NotificationConversionHelper33NotificationToNotificationOptionsERK12NotificationPN10extensions3api13notifications19NotificationOptionsE
    fun:_ZN71NotificationConversionHelperTest_NotificationToNotificationOptions_Test8TestBodyEv
 }
 {
    bug_404182
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN8app_list4test12_GLOBAL__N_122AppListViewTestContext16RunStartPageTestEv
 }
 {
-   bug_415092
+   bug_512466
    Memcheck:Leak
    fun:_Znw*
-   fun:_ZN4base22PosixDynamicThreadPool7AddTaskEPNS_11PendingTaskE
+   fun:_ZN4base22PosixDynamicThreadPool13AddTaskNoLockEPNS_11PendingTaskE
    fun:_ZN4base22PosixDynamicThreadPool8PostTaskERKN15tracked_objects8LocationERKNS_8CallbackIFvvEEE
    fun:_ZN4base12_GLOBAL__N_114WorkerPoolImpl8PostTaskERKN15tracked_objects8LocationERKNS_8CallbackIFvvEEEb
    fun:_ZN4base10WorkerPool8PostTaskERKN15tracked_objects8LocationERKNS_8CallbackIFvvEEEb
 }
 {
    bug_416729
    Memcheck:Unaddressable
    fun:_ZNK5blink6MemberINS_38PlatformSpeechSynthesisUtteranceClientEEcvPS1_Ev
    fun:_ZNK5blink32PlatformSpeechSynthesisUtterance6clientEv
    fun:_ZN5blink15SpeechSynthesis17didFinishSpeakingEPNS_32PlatformSpeechSynthesisUtteranceE
@@ skipping 379 matching lines @@
    fun:_ZN5blink17CSSPropertyParser10parseValueENS_13CSSPropertyIDEbPNS_18CSSParserValueListERKNS_16CSSParserContextERN3WTF6VectorINS_11CSSPropertyELm256ENS7_16DefaultAllocatorEEENS_13StyleRuleBase4TypeE
    fun:_ZN5blink13CSSParserImpl23consumeDeclarationValueENS_19CSSParserTokenRangeENS_13CSSPropertyIDEbNS_13StyleRuleBase4TypeE
    fun:_ZN5blink13CSSParserImpl18consumeDeclarationENS_19CSSParserTokenRangeENS_13StyleRuleBase4TypeE
 }
 {
    bug_509513
    Memcheck:Uninitialized
    fun:_ZNK5blink9FillLayer31computeCachedPropertiesIfNeededEv
    fun:_ZNK5blink9FillLayer29thisOrNextLayersUseContentBoxEv
 }