Rename JTypeOracle.computeHasClinitTarget() -> JTypeOracle.computeClinitTarget().

See: r7868
Suggested by: spoon
http://gwt-code-reviews.appspot.com/184802/show
Review by: spoon


git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@7875 8db76d5a-ed1c-0410-87a9-c151d255dfc7