[Bug Report] Possible error on expandable and searchable data tables

[ghost]

Versions and Environment

Vuetify: 0.17.6
Vue: 2.5.13
Browsers: Chrome 63.0.3239.132
OS: Windows 7

Steps to reproduce

1.- Create a data table that is expandable, and searchable as well, with some items.
2.- Expand one of the last items from the table.
3.- Search for that item on the text field (it should show you that item on the table expanded).
4.- Clear the search term from the textfield (now it shows all items with the expanded item still expanded).
5.- Close the expanded item.

Expected Behavior

Item closes correctly with no errors.

Actual Behavior

Item does close the expanded panel but throws and error on the console: "TypeError: Cannot read property 'classList' of undefined at afterLeave"

Reproduction Link

https://codepen.io/dn1993/pen/baOQVo

Other comments

The error can be triggered on the pen I attached here with the third and fourth items from the table. I tried to override the genExpandedRow function on the VDataTable mixins (body.js) to add a try catch block but I still get the error. This framework is truly awesome, keep up the great work!

[kaijajan]

I encountered exactly the same issue while combining search and expand features.
Error occurs right after manipulate expand feature after searching keyword