Bug 339877 ToolBarManagerRenderer should not dispose of items that weren't created by the rendering engine
1. Window > Open Perspective > CVS Repository Exploring 2. The 'CVS Repositories' view doesn't have the 'Add CVS Repository' tool item. 3. Resizing the view doesn't help. 4. Close the view. 5. Reopen it. 6. Now it's there. Or maybe not, it didn't come back for Paul anyway.
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/ui/workbench/renderers/swt/ToolBarManagerRenderer.java
final ToolBarManager manager, MToolBarContribution contribution) {
		final ToolBarContributionRecord record = new ToolBarContributionRecord(
				toolbarModel, contribution, this);
		if (!record.mergeIntoModel()) {
			return false;
		}
		if (record.anyVisibleWhen()) {
			final IEclipseContext parentContext = modelService
					.getContainingContext(toolbarModel);
			parentContext.runAndTrack(new RunAndTrack() {
				@Override
				public boolean changed(IEclipseContext context) {
					record.updateVisibility(parentContext.getActiveLeaf());
					manager.update(true);
					return true;
				}
			});
		}
		return true;
	}
	private ToolBar createToolbar(final MUIElement element, Composite parent) {
		int orientation = getOrientation(element);
		ToolBarManager manager = getManager((MToolBar) element);
		if (manager == null) {
			manager = new ToolBarManager(orientation | SWT.WRAP | SWT.FLAT
					| SWT.RIGHT);
			linkModelToManager((MToolBar) element, manager);
		}
		ToolBar bar = manager.createControl(parent);
		if (bar.getParent() != parent) {