Bug 123424 browsing perspective does not show some packages in hierarchical mode
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/browsing/PackagesViewHierarchicalContentProvider.java
String key= getKey(frag);
		LogicalPackage lp= (LogicalPackage)fMapToLogicalPackage.get(key);
		if(lp != null){
			lp.remove(frag);
			
			
			
			if (lp.getFragments().length == 1) {
				IPackageFragment fragment= lp.getFragments()[0];
				fMapToPackageFragments.put(key, fragment);
				fMapToLogicalPackage.remove(key);
				
				postRemove(lp);
				Object parent= getParent(fragment);
				if (parent instanceof IPackageFragmentRoot) {
					parent= ((IPackageFragmentRoot)parent).getJavaProject();
				}
				postAdd(fragment, parent);
			}
		} else {
			
			IPackageFragment fragment= (IPackageFragment) fMapToPackageFragments.get(key);
			if (fragment!= null && fragment.equals(frag)) {
				fMapToPackageFragments.remove(key);
				postRemove(frag);
			}
		}
	}
}