fix leaking of open faces destroyed from different thread

6 jobs for thread_local_open_faces_cache in 4 minutes and 27 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Build
passed #2441547
build

00:02:47

passed #2441552
build_android

00:00:46

passed #2441548
build_clang_libcpp

00:02:38

passed #2441551
build_clazy

00:02:55

passed #2441550
build_mingw64_fedora

00:04:26

passed #2441549
build_ubuntu_16_04

00:01:22