Bug 89020 [Undo] Operation throws assertion failure if undo limit is set to 0
I20050324-0800 Unfortunately existing clients of text's undo manager were allowed to set any number without failing. This is no longer possible: an assertion failure occurrs if the limit is smaller than 1. I will add code on my side that will handle the negative numbers but the operation history must allow 0.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
}
		return status;
	}
	/*
	 * Remove the specified operation from the undo and redo history
	 */
	private void remove(IUndoableOperation operation) {
		if (undoList.contains(operation)) {
			undoList.remove(operation);
			internalRemove(operation);
		} else if (redoList.contains(operation)) {
			redoList.remove(operation);
			internalRemove(operation);
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IOperationHistory#removeOperationApprover(org.eclipse.core.commands.operations.IOperationApprover)
	 */
	public void removeOperationApprover(IOperationApprover approver) {
		approvers.remove(approver);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IOperationHistory#removeOperationHistoryListener(org.eclipse.core.commands.operations.IOperationHistoryListener)
	 */
	public void removeOperationHistoryListener(
			IOperationHistoryListener listener) {