[test] Skip some layout tests on V8 side

TBR=mslekova@chromium.org
NOTRY=true

Bug: chromium:879604
Change-Id: I051837bae866f391ec5f1555b845cd66cc9f777a
Reviewed-on: https://chromium-review.googlesource.com/1199285
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55560}

tools/blink_tests/TestExpectations

@@ -3,3 +3,5 @@
 # Turn off Slimming Paint tests on linux.
 [ Linux ] virtual/slimmingpaint/ [ Skip ]
 
+# Several failures since https://crrev.com/c/1196547
+crbug.com/879604 external/wpt/cookies/samesite/ [ Skip ]