Clipboard API: Disable flaky Feature Policy tests outside MacOS.

The tests were failing at a lower rate on other OS's, but it seems
they were indeed failing on other OS's. Generalize the [ Pass Failure ]
TestExpectations from [ Mac ] to all platforms.

Bug: 1104024
Change-Id: I78461aa43041776799930416f261f7271ca52ad5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2311312Reviewed-by: Victor Costan <pwnall@chromium.org>
Commit-Queue: Victor Costan <pwnall@chromium.org>
Commit-Queue: Darwin Huang <huangdarwin@chromium.org>
Auto-Submit: Darwin Huang <huangdarwin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#790628}

third_party/blink/web_tests/TestExpectations

@@ -220,8 +220,8 @@ crbug.com/1074482 external/wpt/clipboard-apis/feature-policy/clipboard-read/clip
 crbug.com/1074482 external/wpt/clipboard-apis/feature-policy/clipboard-read/clipboard-read-enabled-by-feature-policy-attribute-cross-origin-tentative.https.sub.html [ Pass Failure ]
 crbug.com/1074482 external/wpt/clipboard-apis/feature-policy/clipboard-write/clipboard-write-enabled-by-feature-policy-cross-origin-tentative.https.sub.html [ Pass Failure ]
 crbug.com/1074482 external/wpt/clipboard-apis/feature-policy/clipboard-write/clipboard-write-enabled-by-feature-policy-attribute-cross-origin-tentative.https.sub.html [ Pass Failure ]
-crbug.com/1105278 [ Mac ] external/wpt/clipboard-apis/feature-policy/clipboard-write/clipboard-write-enabled-on-self-origin-by-feature-policy.tentative.https.sub.html [ Pass Failure ]
-crbug.com/1104125 [ Mac ] external/wpt/clipboard-apis/feature-policy/clipboard-read/clipboard-read-enabled-on-self-origin-by-feature-policy.tentative.https.sub.html [ Pass Failure ]
+crbug.com/1105278 external/wpt/clipboard-apis/feature-policy/clipboard-write/clipboard-write-enabled-on-self-origin-by-feature-policy.tentative.https.sub.html [ Pass Failure ]
+crbug.com/1104125 external/wpt/clipboard-apis/feature-policy/clipboard-read/clipboard-read-enabled-on-self-origin-by-feature-policy.tentative.https.sub.html [ Pass Failure ]
 
 # This test has a bug in it that prevents it from being able to deal with order
 # differences it claims to support.