[LayoutNG] positioning/abspos-007.xht passes.

Got fixed by
https://chromium-review.googlesource.com/c/chromium/src/+/925601 ,
possibly combined with some other CL, since the trybot didn't detect it.

TBR=kojii@chromium.org

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_layout_tests_layout_ng
Change-Id: I4d7b16e0cbaa67f1b940bdceb1fc7e265a6057e8
Reviewed-on: https://chromium-review.googlesource.com/926122
Commit-Queue: Morten Stenshorne <mstensho@chromium.org>
Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537753}

third_party/WebKit/LayoutTests/FlagExpectations/enable-blink-features=LayoutNG

@@ -1058,7 +1058,6 @@ crbug.com/591099 external/wpt/css/CSS2/normal-flow/block-in-inline-remove-006.xh
 crbug.com/591099 external/wpt/css/CSS2/normal-flow/max-height-percentage-002.xht [ Failure ]
 crbug.com/591099 external/wpt/css/CSS2/normal-flow/max-width-applies-to-005.xht [ Pass ]
 crbug.com/591099 external/wpt/css/CSS2/normal-flow/root-box-001.xht [ Failure ]
-crbug.com/591099 external/wpt/css/CSS2/positioning/abspos-007.xht [ Failure ]
 crbug.com/591099 external/wpt/css/CSS2/positioning/positioning-float-001.xht [ Pass ]
 crbug.com/591099 external/wpt/css/CSS2/text/text-decoration-applies-to-015.xht [ Failure ]
 crbug.com/714962 external/wpt/css/css-backgrounds/background-attachment-local/attachment-local-clipping-color-5.html [ Failure ]

third_party/WebKit/LayoutTests/TestExpectations

@@ -290,7 +290,6 @@ crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/replaced-in
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/replaced-intrinsic-002.xht [ Failure ]
 
 ### virtual/layout_ng/external/wpt/css/CSS2/positioning
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/abspos-007.xht [ Failure ]
 crbug.com/704961 [ Mac ] virtual/layout_ng/external/wpt/css/CSS2/positioning/abspos-027.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/position-relative-035.xht [ Failure ]