HaikuDepot: Keep window position when browsing screenshots

[humdinger]

This is hrev51614.

If there are several screenshots with different sizes for an app, the window jumps around when browsing through them. Instead of centering the screenshot window with the screen (or is it the HaikuDepot main window? I'm on an erlier hrev ATM...), it'd be nicer if the top left corner of the window stayed the same. Then you can rest your mouse on the "Next" button, and just click through all shots.

[jua]

This is a somewhat tricky issue. I generally don't like that the window is being resized when flicking through screenshots, it's distracting. So I'd like to get rid of that entirely. But how to do it is still an open issue. An idea is to pre-load all screenshots in the background and then determine the maximum size and use that troughout... but loading all screenshots before displaying one would take too long.

[humdinger]

I guess having the HDS server provide that info, maybe even including thumbnails for previewing, would complicate things?

[jua]

On the HaikuDepot side it would make things easy, not sure though about the server side...

[jua]

Andrew let me know that the server side already gathers this information, and it's even included in the JSON files and parsed in HaikuDepot into ScreenshotInfo::Width() and Height(). I completely overlooked that before!

So yeah, this is doable.

[jua]

Implemented in hrev51625.

One TODO left: it's still possible for the screenshot window to resize itself to be large than the screen size, this needs to be limited. However, then the bitmap view should also become scrollable, which needs to be implemented.