ticket:9101: CollationRootElements::findPrimary()

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/markus@33382 251d0590-4201-4cf1-90de-194747b24ca1
ticket:9101: minor bug fix

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/markus@33383 251d0590-4201-4cf1-90de-194747b24ca1