fix(core): On mouse pointer click move the scrollbar to correct position

[mlipovaca]

Issue:
Scrollbar is not moving to mouse position when clicked on the track.

What is done to fix it:
Scrollbar is now moving by the calculation to specific (exact) mouse position when clicked on the track.

[mlipovaca]

Please if you can review it @Grsmto

[Grsmto]

Hi @mlipovaca thanks for your contribution. The default behaviour on most browsers seems to be that it does not scroll where the user click but rather scroll down 1 viewport height, which is the behaviour of SimpleBar at the moment.
One difference is that on the default scrollbar you can long press to scroll more (not supported by SimpleBar but could be).
So I think we want to stick to the default behaviour as much as possible.
Do you have any example of the behaviour you are describing and how you came up to want it that way? Thanks.

[mlipovaca]

Hi @Grsmto, thanks for the reply. Here're the differences when you "hold" the click on the navigation bar track and on default browser, it'll keep scrolling until it reaches it, but on simplebar it moves only once and that's it.

Reference:

1. Default browser - https://chicksgold.gyazo.com/c423973d0689bebe71beeef1a5d98c5c
2. Simplebar browser - https://chicksgold.gyazo.com/aec8fa411a33f42af2f74ce66dfb12f4

[mlipovaca]

Any words on this @Grsmto ?