Bug 318713 Duplicate toolbar items (navigate group)
SDK 4.0 - I20100701-1105. 1. start fresh workspace ==> navigate group appears twice which is quite confusing and wastes space.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/ContributionsAnalyzer.java
continue;
			}
			toContribute.add(contribution);
		}
	}
	static boolean isFiltered(MTrimBar trimModel, MTrimContribution contribution) {
		return false;
	}
	public static void gatherToolBarContributions(final MToolBar toolbarModel,
			final List<MToolBarContribution> toolbarContributionList, final String id,
			final ArrayList<MToolBarContribution> toContribute, final ExpressionContext eContext) {
		for (MToolBarContribution toolBarContribution : toolbarContributionList) {
			String parentID = toolBarContribution.getParentId();
			boolean filtered = isFiltered(toolbarModel, toolBarContribution);
			if (filtered || !parentID.equals(id) || !toolBarContribution.isToBeRendered()) {
				continue;
			}
			toContribute.add(toolBarContribution);
		}
	}
	static boolean isFiltered(MToolBar toolbarModel, MToolBarContribution toolBarContribution) {
		return false;
	}
	public static void gatherMenuContributions(final MMenu menuModel,
			final List<MMenuContribution> menuContributionList, final String id,
			final ArrayList<MMenuContribution> toContribute, final ExpressionContext eContext,
			boolean includePopups) {
		boolean menuBar = (((MUIElement) ((EObject) menuModel).eContainer()) instanceof MWindow);
		for (MMenuContribution menuContribution : menuContributionList) {
			String parentID = menuContribution.getParentId();