Re-enable http/.../portals-elements-nesting-after-adoption.js

Disabled due to failure on win10, but test passes now on win10.

Bug: 1009016
Change-Id: I9c530d8fe33e0f06bf2a810fa6958545e195487b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1863569Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Commit-Queue: Mandy Chen <mandy.chen@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#706120}

third_party/blink/web_tests/TestExpectations

@@ -5701,7 +5701,6 @@ crbug.com/1008257 external/wpt/service-workers/service-worker/worker-interceptio
 crbug.com/1008826 [ Mac10.13 ] http/tests/security/frameNavigation/xss-ALLOWED-parent-navigation-change.html [ Pass Failure Timeout ]
 
 # Sheriff 2019-09-30
-crbug.com/1009016 [ Win10 ] http/tests/devtools/portals/portals-elements-nesting-after-adoption.js [ Pass Failure ]
 crbug.com/1003715 [ Win10 ] http/tests/notifications/serviceworker-notification-properties.html [ Pass Failure Timeout ]
 
 # Sheriff 2019-10-01