Android patch: Add exceptions for big5han and gb2312han in genrb.

This change was introduced in Android by the ICU 53 upgrade:

https://android.googlesource.com/platform/external/icu/+/fceb398

Suppression of ICU4J test errors was added for ICU 55:

https://android.googlesource.com/platform/external/icu/+/7b913b1

(cherry picked from commit d9fc98087b091be81a9a50fbff9c0e22855d8dac)

Updated from upstream some "avail" flags for commented-out cases

Test: n/a
Change-Id: I49ff6ee9394d1ad002cb741b8d2bd008fef799de
2 files changed