1a8b6c29aa
utf8_length() from libutils returns -1 when source not contains valid sequence for UTF-8. Fixed to use it and removed the local function isValidUtf8(). Change-Id: If2834ce1d1ae07fd8526ce8bc5df3fd3f44e85c8 Signed-off-by: Homin Lee <suapapa@insignal.co.kr>