[test] Temporarily skip some blink tests for V8 roll

The tests are related to ownkeys with duplicates entries.
The tests will be re-enabled once the test expectations are updated.

Bug: v8:6776
Change-Id: I6a65f1f8085c2339e9e385b6716ea23a203ac79e
Reviewed-on: https://chromium-review.googlesource.com/c/1427459
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#624900}

third_party/blink/web_tests/TestExpectations

@@ -2613,6 +2613,9 @@ crbug.com/906847 inspector-protocol/debugger/debugger-scope-skip-variables-with-
 crbug.com/v8/8672 http/tests/devtools/bindings/suspendtarget-bindings.js [ Skip ]
 crbug.com/v8/8672 http/tests/devtools/bindings/suspendtarget-navigator.js [ Skip ]
 crbug.com/v8/8672 http/tests/devtools/tracing/decode-resize.js [ Skip ]
+crbug.com/v8/6776 virtual/outofblink-cors/external/wpt/fetch/api/headers/headers-record.html [ Skip ]
+crbug.com/v8/6776 external/wpt/fetch/api/headers/headers-record.html [ Skip ]
+crbug.com/v8/6776 virtual/outofblink-cors-ns/external/wpt/fetch/api/headers/headers-record.html [ Skip ]
 
 # These testcases are incorrect, mark them as failing until they're fixed in the testsuite.
 # https://lists.w3.org/Archives/Public/www-style/2016Jan/0275.html