Roll over ICU to 113543

Fix buffer overflow in _canonicalize.

Upstream bug is http://bugs.icu-project.org/trac/ticket/8984

The actual fix is at
 http://codereview.chromium.org/8822005

BUG=chromium:106441
TBR=falken
Review URL: http://codereview.chromium.org/8873031

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@113644 0039d316-1c4b-4281-b951-d872f2087c98