health: use recursive_mutex.
authorYifan Hong <elsk@google.com>
Wed, 3 Oct 2018 00:11:14 +0000 (17:11 -0700)
committerandroid-build-merger <android-build-merger@google.com>
Wed, 3 Oct 2018 00:11:14 +0000 (17:11 -0700)
am: a46c0dae81

Change-Id: I132a9b08d9b3a1f6356436f6a73a90b7b59422c7


Trivial merge