Bug 63389 [projection] Do we need a folding region for the top-level type?
The Java editor is currently defining a folding region for the top-level type. I couldn't find a good use of this folding region and in particular it leads to some visual instability when hovering in the vertical rule in between methods. Therefore I suggest to not add this folding region.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/folding/DefaultJavaFoldingStructureProvider.java
removals.add(existing.next());
					model.replaceAnnotations((Annotation[]) removals.toArray(new Annotation[removals.size()]), additions);
				}
			}
		} finally {
			fCachedDocument= null;
			fCachedModel= null;
			fAllowCollapsing= false;
			fFirstType= null;
			fHasHeaderComment= false;
		}
	}
	private void initializePreferences() {
		IPreferenceStore store= JavaPlugin.getDefault().getPreferenceStore();
		fCollapseInnerTypes= store.getBoolean(PreferenceConstants.EDITOR_FOLDING_INNERTYPES);
		fCollapseImportContainer= store.getBoolean(PreferenceConstants.EDITOR_FOLDING_IMPORTS);
		fCollapseJavadoc= store.getBoolean(PreferenceConstants.EDITOR_FOLDING_JAVADOC);
		fCollapseMethods= store.getBoolean(PreferenceConstants.EDITOR_FOLDING_METHODS);
		fCollapseHeaderComments= store.getBoolean(PreferenceConstants.EDITOR_FOLDING_HEADERS);
	}
	private Map computeAdditions(IParent parent) {
		Map map= new LinkedHashMap(); 
		try {
			computeAdditions(parent.getChildren(), map);
		} catch (JavaModelException x) {
		}
		return map;
	}
	private void computeAdditions(IJavaElement[] elements, Map map) throws JavaModelException {
		for (int i= 0; i < elements.length; i++) {