[Autocomplete] Make the scrollbar stay in current position on mouse expand

[ajlamarc]

As shown in this CSB, the scrollbar returns to top on scrolling down the list with mouse.

https://codesandbox.io/s/confident-kare-5n6i6

removing the else-if condition in the following if statement removes the reason for this scrollbar adjustment, the scrollbar will now stay in its current position.

if (listboxNode.scrollHeight > listboxNode.clientHeight && reason !== 'mouse')

[mui-bot]

Details of bundle changes

Generated by 🚫 dangerJS against 1dca529

[michaldudak]

This breaks the scrolling behavior when the highlight moves up. See https://deploy-preview-30711--material-ui.netlify.app/components/autocomplete/#combo-box - when you scroll to the middle then move the highlight up, the highlighted item is not visible.

Also, the code you removed in this PR was added in #19305 to improve scrolling on grouped options.

[siriwatknp]

👋 The migration PR has been merged.

Please follow these steps to make sure that the contents are all updated. (Sorry for the inconvenience)

1. pull latest master from upstream to your branch
2. if your PR has changes on the *.md or demo files, you are likely to encounter conflict because all of them have been moved to the new folder.
   2.1 revert the change on those markdown files you did
   2.2 pull latest master from upstream (you should not see conflict)
   2.3 make the changes again at docs/data/material/*
3. run yarn docs:api
   • you might see the changes in docs/pages/material/api/* if your PR touches some of the components
   • it is okay if there is no changes

If you are struggle with the steps above, feel free to tag @siriwatknp

[mnajdova]

@ajlamarc please open an issue before creating a pull request, so that we can discuss the solution to the problem first. Thank you!