Sorting custom styling sample does not show sort indicators.

[MayaKirova]

Description

The sample seems to show custom styling for sorting indicator but there's no sorting indicator visible in the sample.

Steps to reproduce

1. Open the sample under: https://www.infragistics.com/products/ignite-ui-angular/angular/components/grid/sorting#demo
   also the tree grid one:
   https://www.infragistics.com/products/ignite-ui-angular/angular/components/treegrid/sorting#demo

Result

You cannot see the sort indicator.

Expected result

You should see sorting indicator with custom style.

Attachments

Attach a sample if available, and screenshots, if applicable.

[MayaKirova]

I think this is something related to the custom theme. The custom color does get applied but for some reason opacity becomes 0 so it is not visible. This does not happen when there's no custom theme applied.