fix some edge cases in garbage collection logic and allow files with garbage to leave upsched
fix some edge cases in garbage collection logic and allow files with garbage to leave upsched

git-svn-id: ae92b08b608af1c8cefa3e10d2325ea527204e07@17093 3eda493b-6a19-0410-b2e0-ec8ea4dd8fda

pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable,pscedu/slash2-stable