Zygote : Block SIGCHLD during fork. am: b1f1209d9a am: 35b8453338 am: 14bd75fa79 am: 50b0c3be57  -s ours am: e1e735bcb9 am: 072b70bae3 am: ba6d5ee377 am: f3f784853d am: 8ea47824fa am: 2f2611636b
am: 86e1929551

Change-Id: Ic1a9c733b811ab04cc0024956998137a39edeee5