Fix two more compile errros on Windows.

umutex.h and wintz.c have two compile errors on Windows.  The former
issue was fixed in the upstream, but the latter is not. I reported
the latter to the upstream (see README.chromium)

BUG=132145
TEST=Can build on Windows with icu52.
R=mark@chromium.org
TBR=mark@chromium.org

Review URL: https://codereview.chromium.org/256183002

git-svn-id: http://src.chromium.org/svn/trunk/deps/third_party/icu52@266901 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
4 files changed