ticket:9440: gcc compiler warning cleanup.

git-svn-id: http://source.icu-project.org/repos/icu/icu/trunk/source@33279 251d0590-4201-4cf1-90de-194747b24ca1
ticket:9637: make new DateFormat skeleton constants public API

git-svn-id: http://source.icu-project.org/repos/icu/icu/trunk/source@33280 251d0590-4201-4cf1-90de-194747b24ca1
ticket:9935: rename si_value variable to avoid collision with #define in Android system header

git-svn-id: http://source.icu-project.org/repos/icu/icu/trunk/source@33281 251d0590-4201-4cf1-90de-194747b24ca1