switch deps to openjdk, since that's the best supported on Debian

debian/control

@@ -3,13 +3,13 @@ Section: contrib/misc
 Priority: optional
 Maintainer: Marin Atanasov Nikolov <mra@melexis.com>
 Build-Depends: debhelper (>> 7)
-Build-Depends-Indep: sun-java6-jdk
+Build-Depends-Indep: openjdk-6-jdk
 Standards-Version: 3.8.3
 Homepage: http://code.google.com/p/gerrit/
 
 Package: gerrit
 Architecture: all
-Depends: ${misc:Depends}, adduser, sun-java6-jre, git-core
+Depends: ${misc:Depends}, adduser, openjdk-6-jre, git-core
 Description: Web based code review and project management for Git based projects
  Gerrit is a web based code review system, facilitating online
  code reviews for projects using the Git version control system.