ticket:9101: redo finding weights after root CEs

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/markus@33686 251d0590-4201-4cf1-90de-194747b24ca1
ticket:9101: un-break CollationTest

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/markus@33705 251d0590-4201-4cf1-90de-194747b24ca1