Add read/write methods for vectors

Also a readString16 with the expected semantics.

Test: Unit tests pass
Bug: 25012838
Signed-off-by: Casey Dahlin <sadmac@google.com>

(cherry picked from commit 451ff582d730e27f4e22d9f158f8ee24d1bc2729)

Change-Id: Iaecde0e94c4cd11126b7efbc2d9876ddae16b090
2 files changed