Bug 314685 EModelService's findElements(MUIElement, String, Class<T>, List<String>) method can return duplicates
I'm getting two editors in the returned list that's pointing at the same thing. The returned collection is a List and not a Set but this feels wrong.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/ModelServiceImpl.java
int relToIndex = relTo.getParent().getChildren().indexOf(relTo);
				if (newFirst) {
					curTile.getChildren().add(relToIndex, toInsert);
				} else {
					curTile.getChildren().add(relToIndex + 1, toInsert);
				}
				
				int relToWeight = 100;
				if (relTo.getContainerData() != null) {
					try {
						relToWeight = Integer.parseInt(relTo.getContainerData());
					} catch (NumberFormatException e) {
					}
				}
				int toInsertWeight = (int) ((ratio / 100.0) * relToWeight + 0.5);
				relToWeight = relToWeight - toInsertWeight;
				relTo.setContainerData(Integer.toString(relToWeight));
				toInsert.setContainerData(Integer.toString(toInsertWeight));
			}
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.e4.workbench.modeling.EModelService#detach(org.eclipse.e4.ui.model.application
	 * .MPartSashContainerElement)
	 */
	public void detach(MPartSashContainerElement element) {