Bug 81421 Closing a project with open editors leaves stale elements in Package Explorer's working set layout
I20041216-0800 Closing a project with open editors leaves stale elements in Package Explorer's working sets mode. This only affects CUs not normal resources.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/workingsets/HistoryWorkingSetUpdater.java
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