Merge \\\\\\\\\\\"DO NOT MERGE libutils/Unicode.cpp: Correct length...

Merge \\\\\\\\\\\"DO NOT MERGE libutils/Unicode.cpp: Correct length computation and add checks for utf16->utf8\\\\\\\\\\\" into lmp-dev am: 8d2d6ced  -s ours am: 71da8e75 am: 5e03ed1d am: b00e3603  -s ours am: 72bad95d am: ae21a253 am: 1062106a am: 9d6d33db  -s ours am: 8c335e28 am: c5259155
am: a1d67c3b  -s ours

Change-Id: Icba5257f1398b07c25c4a7d78fadd95ee87f5253