Use ICU in libandroidicu

libicuuc and libicui18n are moved into APEX, but
they have no stable ABI due to the version suffix.

Use libandroidicu which provides stable symbol.
See http://r.android.com/801855 for libandroidicu implementation.

Bug: 117094880
Test: m checkbuild
Merged-In: I2da65a9ac14ac4e953ed57ec253355811099dde8
Change-Id: I2da65a9ac14ac4e953ed57ec253355811099dde8
(cherry picked from commit 31e5d116)