DO NOT MERGE libutils/Unicode.cpp: Correct length computation and add checks for utf16->utf8 am: 5fce0542b6 am: d0ad14ca21 am: 3841c92912  -s ours am: 247ac63c69  -s ours
am: 6179f1a56e

Change-Id: I1622017cea3f29fc17e8f75f0cfa77c786a08937