Bug 303831 Warnings logged when trying to merge changes to an MPart's 'closeable' attribute
Warnings are printed out to syserr. --- WARNING: Unknown feature found, reconciliation may fail: Part#closeable
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/XMLModelReconciler.java
private final Object object;
		private final Object after;