REGRESSION: [ Mac WK2 ] tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-borders.html is a flaky failure

[Truitt Savell]

tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-borders.html 

This test began failing recently. I am able to reproduce the failure with this command:

run-webkit-tests --iterations 2000 --exit-after-n-failures 1 --exit-after-n-crashes-or-timeouts 1 --debug-rwt-logging --no-retry --force --no-build -f tiled-drawing/scrolling/scroll-iframe-latched-selects.html

History:
https://results.webkit.org/?suite=layout-tests&test=tiled-drawing%2Fscrolling%2Fscroll-snap%2Fscroll-snap-mandatory-borders.html

Diff:
--- /Volumes/Data/slave/catalina-debug-tests-wk2/build/layout-test-results/tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-borders-expected.txt
+++ /Volumes/Data/slave/catalina-debug-tests-wk2/build/layout-test-results/tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-borders-actual.txt
@@ -4,10 +4,11 @@
 Testing scroll-snap snap for horizontalTarget:
 PASS div honored snap points.
 Testing scroll-snap glide for verticalTarget:
-PASS div scrolled to next window.
+FAIL div did not honor snap points. Expected 300, but got 0
 Testing scroll-snap snap for verticalTarget:
 PASS div honored snap points.
 PASS successfullyParsed is true
+Some tests failed.
 
 TEST COMPLETE

[Radar WebKit Bug Importer]

<rdar://problem/60641337>

[Simon Fraser (smfr)]

Pretty sure that https://trac.webkit.org/changeset/258753/webkit fixed this.

*** This bug has been marked as a duplicate of bug 165196 ***