allow init to run mke2fs tools to format partitions

Test: let fs_mgr format a damaged /data partition
Bug: 35219933
Change-Id: If92352ea7a70780e9d81ab10963d63e16b793792
diff --git a/private/file_contexts b/private/file_contexts
index c46ba59..36066df 100644
--- a/private/file_contexts
+++ b/private/file_contexts
@@ -17,6 +17,8 @@
 /charger            u:object_r:rootfs:s0
 /init               u:object_r:init_exec:s0
 /sbin(/.*)?         u:object_r:rootfs:s0
+/sbin/e2fsdroid     u:object_r:e2fs_exec:s0
+/sbin/mke2fs        u:object_r:e2fs_exec:s0
 
 # For kernel modules
 /lib(/.*)?          u:object_r:rootfs:s0
@@ -450,6 +452,7 @@
 /sys/devices/virtual/block/zram\d+(/.*)?     u:object_r:sysfs_zram:s0
 /sys/devices/virtual/block/zram\d+/uevent    u:object_r:sysfs_zram_uevent:s0
 /sys/devices/virtual/misc/hw_random(/.*)?    u:object_r:sysfs_hwrandom:s0
+/sys/fs/ext4/features(/.*)?                  u:object_r:sysfs_fs_ext4_features:s0
 /sys/power/wake_lock -- u:object_r:sysfs_wake_lock:s0
 /sys/power/wake_unlock -- u:object_r:sysfs_wake_lock:s0
 /sys/kernel/uevent_helper --	u:object_r:usermodehelper:s0