DO NOT MERGE libutils/Unicode.cpp: Correct length computation and add checks for utf16->utf8 am: 2806397d1e am: 8c9d02551c am: 28f28ce635  -s ours am: f611765aaf am: 207717bde6
am: dc5a96f5b3

Change-Id: I02b02a89f381c1cadff3b4702e1ff8e8850b219e