Mark some virtual/composite-bgcolor-animation/ no longer crash

I believe that these layout tests were fixed by this CL:
https://chromium-review.googlesource.com/c/chromium/src/+/2579949

Now there is only one test that needs investigation.

Bug: 1150468
Change-Id: I4ea59de2068fa13890a4578450ec061c28b40cc0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2605482Reviewed-by: Yi Gu <yigu@chromium.org>
Commit-Queue: Xida Chen <xidachen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840141}

third_party/blink/web_tests/FlagExpectations/composite-after-paint

@@ -63,8 +63,7 @@ crbug.com/1123189 virtual/threaded-composited-iframes/external/wpt/is-input-pend
 
 crbug.com/1124979 compositing/video/video-controls-layer-creation.html [ Pass Failure ]
 
-crbug.com/1150468 virtual/composite-bgcolor-animation/external/wpt/css/css-backgrounds/* [ Skip ]
-crbug.com/1150468 virtual/composite-bgcolor-animation-hidpi/external/wpt/css/css-backgrounds/hidpi/* [ Skip ]
+crbug.com/1150468 virtual/composite-bgcolor-animation/external/wpt/css/css-backgrounds/animations/one-element-animation.html [ Crash ]
 
 crbug.com/1157199 external/wpt/css/css-paint-api/column-count-crash.https.html [ Crash ]
 crbug.com/1157199 virtual/off-main-thread-css-paint/external/wpt/css/css-paint-api/column-count-crash.https.html [ Crash ]