ICUTranscoder::transcodeFrom() expects ICU function ucnv_toUnicode to return

an extra element in fSrcOffsets to allow us to figure out the last char size, which
in fact it is not.  The fix is to compute the last char size ourselves using the total bytes used.
Fixed by Matt Lovett.


git-svn-id: https://svn.apache.org/repos/asf/xerces/c/trunk@172541 13f79535-47bb-0310-9956-ffa450edef68