position: collision should take margin into account

[bhollis]

The position utility should take into account margins when performing collisions (or offer some other way of offsetting the collision box from the element itself). This way you could prevent positioned elements from getting too close to the edge of the screen. This is especially useful when the positioned element uses -moz-box-shadow, since a shadow that falls outside the page will cause scrollbars.

[bhollis]

I addressed this in ​http://github.com/bhollis/jquery-ui/commit/d2ffcac0adb79c3415ec3148f604f9de15c7cf0a and have sent a pull request.

[bhollis]

I'd really love to see this patch committed - without it there's no good way to use drop shadows on positioned elements or pop stuff up that doesn't go to the exact edge of the screen.

[Jörn Zaefferer]

Tested that commit. Testsuite fails on IE8.

[bhollis]

Sorry about that! I've fixed this in ​http://github.com/bhollis/jquery-ui/commit/e9ce8e7b60644f9fb504d2e9684bd61f8c97388d

[bhollis]

I rebased the IE8 fix and the original patch together into one commit on top of the latest master if that makes it easier to pull: ​http://github.com/bhollis/jquery-ui/commit/118a2f86a1c74ab5f42a1700512ec33667296f12

[Scott González]

Fixed in ​4b9d5d1. Thanks bhollis.

[Ben Hollis]

Position: Take margin into account when performing collisions. Fixes #5766 - position: collision should take margin into account.

Changeset: 4b9d5d1b5bd36726c6e49b105c0f75649cca1ae4