fsync after block device writes

When markBoolSuccessful is invoked, we update
the partition table. These writes should be
synced before merge operation is resumed post OTA.
If not, any crash before these writes are landed to
backing storage will lead to incorrect switching of
slots.

BUG: 175711601
BUG: 177652253
Test: Verify slot switching correctly after crash when merge in progress
Signed-off-by: Akilesh Kailash <akailash@google.com>
Change-Id: I2da9286490d5d063df0c9d4dc491e0fbf28f51bb
(cherry picked from commit fd0c59fdae3e12b7e09b5b3911987611ed997f6b)
1 file changed