Skip manual wpt/appmanifest/shortcuts-member tests.

And remove the meaningless screenshot expectations.

Change-Id: I3ecdde35d8d1c9acd8a18a24813a25271e5245f9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2549944Reviewed-by: Stephen McGruer <smcgruer@chromium.org>
Commit-Queue: Morten Stenshorne <mstensho@chromium.org>
Cr-Commit-Position: refs/heads/master@{#829627}

third_party/blink/web_tests/NeverFixTests

@@ -1428,6 +1428,12 @@ external/wpt/FileAPI/FileReader/test_notreadableerrors-manual.html [ Skip ]
 external/wpt/FileAPI/FileReader/test_securityerrors-manual.html [ Skip ]
 external/wpt/FileAPI/url/url_createobjecturl_file_img-manual.html [ Skip ]
 external/wpt/accelerometer/LinearAccelerationSensor-shake-threshold-manual.https.html [ Skip ]
+external/wpt/appmanifest/shortcuts-member/shortcuts-member-manual.html [ Skip ]
+external/wpt/appmanifest/shortcuts-member/shortcuts-member-skip-for-empty-name-manual.html [ Skip ]
+external/wpt/appmanifest/shortcuts-member/shortcuts-member-skip-for-invalid-url-manual.html [ Skip ]
+external/wpt/appmanifest/shortcuts-member/shortcuts-member-skip-for-out-of-scope-url-manual.html [ Skip ]
+external/wpt/appmanifest/shortcuts-member/shortcuts-member-skip-for-undefined-name-manual.html [ Skip ]
+external/wpt/appmanifest/shortcuts-member/shortcuts-member-skip-for-undefined-url-manual.html [ Skip ]
 external/wpt/audio-output/setSinkId-manual.https.html [ Skip ]
 external/wpt/battery-status/battery-charging-manual.https.html [ Skip ]
 external/wpt/battery-status/battery-plugging-in-manual.https.html [ Skip ]