[Select] MuiNativeSelect-iconOpen is not applied when control is opened

Duplicates

• I have searched the existing issues

Latest version

• I have tested the latest version

Steps to reproduce 🕹

Link to live example:
The issue is visible on the component's demo page in the documentation: Select.
Steps:

1. Open the demo page on a mobile device or a browser's emulated mobile view
2. Click on the Native Select demo component

Current behavior 😯

The icon does not rotate because the MuiNativeSelect-iconOpen class is not applied to the icon when the control is opened.

Expected behavior 🤔

The icon rotates because the MuiNativeSelect-iconOpen class is applied to the icon, just like it works for the regular Select component.

Context 🔦

I was trying to implement a custom dropdown icon and overriding the MuiNativeSelect-iconOpen did not do anything despite being mentioned on the component's api documentation, leading me to notice that said class is never actually applied to the icon.

Your environment 🌎

Irrelevant considering this issue also occurs on the component's demo page.

Start with the Native Select implementation and compare it with the regular Select behavior described in the issue. Reproduce the problem from the Select demo page on a mobile device or emulated mobile view; done means the MuiNativeSelect-iconOpen class is applied when the native control opens and the icon rotates.