Bug 1949894 [wpt PR 50886] - Handle overlay scrollbars gracefully in auto-scrollbars.html, a=testonly

Automatic update from web-platform-tests
Handle overlay scrollbars gracefully in auto-scrollbars.html

The WPT test auto-scrollbars.html depends on the browser not having
overlay scrollbars. This test has been consistently failing on mac due
to failing this assertion:
https://luci-milo.appspot.com/ui/tests/p/chromium/rules/751e05390273c6cfc8bf07cc5d245522?annotated=false&historyTimeRange=30d&selectedMetrics=human-cls-failed-presubmit%2Ccritical-failures-exonerated%2Cfailures%2Cbuilds-failed-due-to-flaky-tests&tab=recent-failures&groupBy=os

This CL changes the file so that tests are skipped when overlay
scrollbars are detected instead of crashing after failing the
assertion.

Crbug 398159676 was created as a follow up of this CL to make our
infra handle assert_implements_optional as not failures. After that
work is completed, this CL will be reverted and the assert will be
restored.

Bug: 398159676, 398159680
Change-Id: Ibe6efb7dce6528f6eb397a116ab45312e9edd5cc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6288285
Reviewed-by: Xianzhu Wang <wangxianzhuchromium.org>
Commit-Queue: Gaston Rodriguez <gastonrmicrosoft.com>
Cr-Commit-Position: refs/heads/main{#1423390}

--

wpt-commits: e5d62457ed30f84cda5ac3665e7de05604e8c1c2
wpt-pr: 50886

UltraBlame original commit: ccf2443496efb1b02d651d40d17df066eb6f3117

Author: marco-c

testing/web-platform/tests/css/css-conditional/container-queries/auto-scrollbars.html

@@ -288,26 +288,19 @@
 (
 )
 ;
-assert_implements_optional
-(
+}
+)
+;
+const
+has_overlay_scrollbars
+=
 precondition
 .
 clientWidth
-<
+=
+=
+=
 100
-"
-Tests
-do
-not
-work
-with
-overlay
-scrollbars
-"
-)
-;
-}
-)
 ;
 let
 initialScrollerWidth
@@ -323,6 +316,12 @@
 =
 >
 {
+if
+(
+has_overlay_scrollbars
+)
+return
+;
 assert_equals
 (
 getComputedStyle
@@ -375,6 +374,12 @@
 =
 >
 {
+if
+(
+has_overlay_scrollbars
+)
+return
+;
 inner
 .
 style