Bug 88838 [Undo] - API cleanup - remove IContextConsultingOperationApprover
Early on this was involved in scenarios where editors examined other operations. This is no longer used. Operation approvers generally apply to all contexts and are installed at the OperationHistory level. Until there is a concrete need for this API it should be removed. It is gratuitous at this point.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
*/
	public boolean canUndo(IUndoContext context) {
		
		IUndoableOperation operation = getUndoOperation(context);
		return (operation != null && operation.canUndo());
	}
	/**
	 * Check the redo limit before adding an operation.  In theory the redo limit
	 * should never be reached, because the redo items are transferred from the undo
	 * history, which has the same limit.  The redo history is cleared whenever a new
	 * operation is added.  We check for completeness since implementations may change
	 * over time.
	 */
	private void checkRedoLimit(IUndoableOperation operation) {
		IUndoContext [] contexts = operation.getContexts();
		for (int i=0; i<contexts.length; i++) {
			int limit = getLimit(contexts[i]);
			if (limit > 0) forceRedoLimit(contexts[i], limit - 1);
		}
	}
	/**
	 * Check the undo limit before adding an operation.
	 */
	private void checkUndoLimit(IUndoableOperation operation) {
		IUndoContext [] contexts = operation.getContexts();
		for (int i=0; i<contexts.length; i++) {
			int limit = getLimit(contexts[i]);
			if (limit > 0) forceUndoLimit(contexts[i], limit - 1);
		}
	}