Sheriffing: Generalize expectation for pointerevent_mouse-pointer-preventdefault.html.

It is also timing out on Mac 10.12:
  https://ci.chromium.org/p/chromium/builders/ci/Mac10.12%20Tests/38444

Bug: 626703
Tbr: pkasting@chromium.org
Change-Id: Ib62dbe51a54f888fd9bd2164fd754d553f13dfbc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2476955Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Jeremy Roman <jbroman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#817611}

third_party/blink/web_tests/TestExpectations

@@ -2647,9 +2647,7 @@ crbug.com/626703 [ Mac11.0 ] virtual/threaded/external/wpt/animation-worklet/wor
 crbug.com/626703 [ Mac ] external/wpt/web-locks/query-ordering.tentative.https.html [ Pass Failure ]
 crbug.com/626703 external/wpt/fetch/connection-pool/network-partition-key.html [ Timeout ]
 crbug.com/626703 [ Mac10.15 ] external/wpt/html/browsers/the-window-object/apis-for-creating-and-navigating-browsing-contexts-by-name/open-features-tokenization-top-left.html [ Timeout ]
-crbug.com/626703 [ Mac10.13 ] external/wpt/pointerevents/compat/pointerevent_mouse-pointer-preventdefault.html [ Timeout Pass Failure ]
-crbug.com/626703 [ Mac10.14 ] external/wpt/pointerevents/compat/pointerevent_mouse-pointer-preventdefault.html [ Timeout ]
-crbug.com/626703 [ Mac10.15 ] external/wpt/pointerevents/compat/pointerevent_mouse-pointer-preventdefault.html [ Timeout Pass Failure ]
+crbug.com/626703 [ Mac ] external/wpt/pointerevents/compat/pointerevent_mouse-pointer-preventdefault.html [ Timeout Pass Failure ]
 crbug.com/626703 [ Mac10.15 ] virtual/threaded/external/wpt/animation-worklet/worklet-animation-with-scroll-timeline-root-scroller.https.html [ Failure ]
 crbug.com/626703 [ Mac10.14 ] virtual/off-main-thread-css-paint/external/wpt/css/css-paint-api/valid-image-before-load.https.html [ Failure ]
 crbug.com/626703 external/wpt/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/pageshow-event.window.html [ Timeout ]