[LayoutNG] Remove an incorrect crash expectation line

r570447 already fixed the crash in
fast/block/positioning/rtl-static-positioning-inline-block.html, and
removed the crash expectation line. The crash line was added back in
r571221 due to rebase errors.

Hence, this patch removes the crash line.

Bug: 591099
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng
Change-Id: Ieba2a9138e47b5f2e0bb91bd0e387412c8a44d6e
Reviewed-on: https://chromium-review.googlesource.com/1119152
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Commit-Queue: Emil A Eklund <eae@chromium.org>
Reviewed-by: Emil A Eklund <eae@chromium.org>
Reviewed-by: Aleks Totic <atotic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#571303}

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

@@ -28,9 +28,6 @@ crbug.com/636993 fast/writing-mode/vertical-baseline-alignment.html [ Failure ]
 crbug.com/854840 fast/table/backgr_border-table-quirks-collapsed-border.html [ Failure ]
 crbug.com/854840 fast/table/backgr_border-table-quirks.html [ Failure ]
 
-# Fails to layout everything with 'position:absolute' inside inline block
-crbug.com/855749 fast/block/positioning/rtl-static-positioning-inline-block.html [ Crash ]
-
 # Fails due to incorrect offset mapping using cache.
 crbug.com/636993 external/wpt/css/css-text/word-break/word-break-break-all-005.html [ Failure ]
 crbug.com/636993 external/wpt/css/css-text/word-break/word-break-normal-hi-000.html [ Failure ]