Clean up js-test use in scroll-snap tests

Clean up js-test use in scroll-snap tests
https://bugs.webkit.org/show_bug.cgi?id=148046

Reviewed by Brent Fulgham.

* tiled-drawing/scrolling/scroll-snap/scroll-snap-iframe-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-iframe.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-2d-overflow-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-2d-overflow.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-borders-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-borders.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-horizontal-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-horizontal.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-slow-horizontal-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-slow-horizontal.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-slow-vertical-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-slow-vertical.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-vertical-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-vertical.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-overflow-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-overflow-stateless-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-overflow-stateless.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-overflow.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-padding-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-padding.html:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-rotated-expected.txt:
* tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-rotated.html:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@188509 268f45cc-cd09-0410-ab3c-d52691b4dbfc