Bug 117601 [Undo] - update org.eclipse.core.commands.operations to use new equinox common utils
org.eclipse.core.commands.operations.DefaultOperationHistory - synchronizes its own listener list org.eclipse.core.commands.internal.util. - implements its own Assert. These should be updated to use the new support in org.eclipse.equinox.common
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
}
		
		return status;
	}
	/*
	 * Filter the specified list to include only the specified undo context.
	 */
	private IUndoableOperation[] filter(List list, IUndoContext context) {
		/*
		 * This method is used whenever there is a need to filter the undo or
		 * redo history on a particular context. Currently there are no caches
		 * kept to optimize repeated requests for the same filter. If benchmarks
		 * show this to be a common pattern that causes performances problems,
		 * we could implement a filtered cache here that is nullified whenever
		 * the global history changes.
		 */
		List filtered = new ArrayList();
		Iterator iterator = list.iterator();
		synchronized (undoRedoHistoryLock) {
			while (iterator.hasNext()) {
				IUndoableOperation operation = (IUndoableOperation) iterator
						.next();
				if (operation.hasContext(context)) {
					filtered.add(operation);
				}
			}
		}
		return (IUndoableOperation[]) filtered
				.toArray(new IUndoableOperation[filtered.size()]);
	}