D13284: [decorations] Let KDecoration plugins recommend a border size per default

ngraham added a comment.


  In D13284#460836 <https://phabricator.kde.org/D13284#460836>, @davidedmundson wrote:
  
  > (This comment is somewhat offtopic from this exact patch, but I can't find the relevant thread)
  >
  > In order to facilitate one of the (legitimate) concerns with this patch I added support for kwin to support 9 different resize cursors.
  >  i.e <-- or --> instead of <-->
  >
  > This way if you have two windows close to each other you know what you're resizing.
  >
  > I asked for the relevant icons in breeze to complete that feature and resolve the concern nearly a year ago, https://bugs.kde.org/show_bug.cgi?id=395247 they still haven't landed !
  
  
  I'll see if I can rouse VDG to get us some appropriate icons. However I don't think this is a blocker because the rule is pretty simple: for a shared /nearby edge, the window on top is the one that gets resized. This is visually hinted by the fact that the upper window shadows the lower one. It's also the behavior seen on macOS, Windows, and GNOME, so people are pretty accustomed to it and it doesn't seem to be a usability issue. We can do better of course, but I think it's not a blocker.

REPOSITORY
  R108 KWin

BRANCH
  borderSizeRecommend

REVISION DETAIL
  https://phabricator.kde.org/D13284

To: romangg, #kwin, #plasma, #vdg, ngraham
Cc: pino, filipf, anemeth, davidedmundson, abetts, graesslin, ngraham, zzag, kwin, jraleigh, GB_2, mkulinski, ragreen, jackyalcine, Pitel, iodelay, bwowk, ZrenBot, alexeymin, lesliezhai, ali-mohamed, hardening, jensreuterberg, sebas, apol, mart