Change expectation file of pointerevent_coalesced_events_attributes.html

for Mac 10.13

The wpt test pointerevent_coalesced_events_attributes.html is flaky on
Mac10.13 Tests bot, because its running result is different from the
default expectation file. Changing third_party/blink/web_tests/platform/
mac/external/wpt/pointerevents/extension/pointerevent_coalesced_events_attributes-expected.txt
which is used by Mac 10.13 bot.
https://test-results.appspot.com/data/layout_results/mac-rel/216117/webkit_layout_tests%20%28retry%20shards%20with%20patch%29/layout-test-results/results.html

Bug: 1015254
Change-Id: I3f774c84e20e30244ce45bc5ab295e1d6260f597
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1873382Reviewed-by: Robert Ma <robertma@chromium.org>
Commit-Queue: Lan Wei <lanwei@chromium.org>
Cr-Commit-Position: refs/heads/master@{#708620}

third_party/blink/web_tests/TestExpectations

@@ -5734,7 +5734,6 @@ crbug.com/1014950 [ Mac ] virtual/threaded/http/tests/devtools/tracing/timeline-
 crbug.com/1015187 [ Linux Mac ] virtual/cross-origin-embedder-policy/external/wpt/html/cross-origin-embedder-policy/none.https.html [ Pass Failure ]
 
 # Sheriff 2019-10-18
-crbug.com/1015254 [ Mac ] external/wpt/pointerevents/extension/pointerevent_coalesced_events_attributes.html [ Pass Failure ]
 crbug.com/1015859 [ Linux ] http/tests/devtools/a11y-axe-core/performance/landing-page-a11y-test.js [ Pass Failure ]
 crbug.com/1015975 media/video-currentTime.html [ Pass Failure ]
 crbug.com/1015975 virtual/audio-service/media/video-currentTime.html [ Pass Failure ]

third_party/blink/web_tests/platform/mac/external/wpt/pointerevents/extension/pointerevent_coalesced_events_attributes-expected.txt

@@ -4,7 +4,7 @@ PASS touch pointercancel should not have any coalesced events
 PASS touch pointerover should not have any coalesced events
 PASS touch pointerenter should not have any coalesced events
 PASS touch pointerdown should not have any coalesced events
-PASS touch pointermove should have >2 coalesced events as main thread is busy.
+FAIL touch pointermove should have >2 coalesced events as main thread is busy. assert_greater_than: pointermove should have at least 2 coalesced events. expected a number greater than 1 but got 1
 PASS touch pointermove coalesced events should all be marked as trusted.
 PASS touch time stamps of coalesced events must be ascending.
 PASS touch pointermove coalesced events should all bubbles and cancelable as false.