Fix ProgressBar and Slider one more time
ProgressBar: Fix rendering in RTL mode
Using flipped visualPosition for content width was blatantly wrong for Breeze style. But it was done (by me) during Qt 5 times, and Qt 5 is known for partially broken un-mirroring behavior, so it was harder test.
Also, let's borrow that little inverted/reverse trick from Fusion style.
Slider: Fix tickmarks in RTL mode, this time for real-real
Why over-complicating things, when you could just call a library function with an extra argument all along.
Slider: Fix focus ring positioning
This isn't perfect, and focus frame can still be off by 1px for RTL sliders, but I'm' out of ideas how to make it better.
I used a scratch project with a couple of sliders to test tickmarks and focus ring. See $2791