[Bug Report]empty table scroll issue with attribute 'fixed' and 'show-summary'

[zhaoziji]

Environment

mac 10.14.6 / chrome 83.0.4103.97 / vue 2.6.10

Reproduction link

https://run.iviewui.com/sJMMk0Fd

Steps to reproduce

Create an iview table with atrribute 'fixed' and 'show-summary', and there is not any data ( list=[] ). The console will print the exception information when I try to move the horizontal scroll bar.

What is expected?

The iview framework can handle and disable this not necessary exception information.

What is actually happening?

The console will print the exception information when I try to move the horizontal scroll bar.