Fix another buffer overflow bug in ICU

This is a 'hot' fix and a better patch will be made in the upstream and will be merged down later.  The investigation and the patch by tsepez.

BUG=114342
TEST=See the bug.
TBR=tsepez
Review URL: https://chromiumcodereview.appspot.com/9415012

git-svn-id: http://src.chromium.org/svn/trunk/deps/third_party/icu46@122360 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
3 files changed