Mark some Form suggestion tests flaky again on Win 7

Looks like following tests are still frequently failing on Win 7
fast/forms/suggestion-picker/date-suggestion-picker-appearance-rtl.html
fast/forms/suggestion-picker/week-suggestion-picker-appearance-rtl.html
fast/forms/suggestion-picker/datetimelocal-suggestion-picker-appearance-with-scroll-bar.html
fast/forms/suggestion-picker/time-suggestion-picker-appearance-with-scroll-bar.html
fast/forms/suggestion-picker/time-suggestion-picker-appearance-locale-hebrew.html
fast/forms/suggestion-picker/month-suggestion-picker-appearance-rtl.html

https://ci.chromium.org/p/chromium/builders/ci/Win7%20Tests%20%281%29

Bug: 1043488
Change-Id: I8d4c645528ee72ec2c5e031437838ac8358e5650
Tbr: masonfreed@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2596905Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Kinuko Yasuda <kinuko@chromium.org>
Auto-Submit: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#837980}

third_party/blink/web_tests/TestExpectations

@@ -5906,3 +5906,11 @@ crbug.com/1158672 [ Mac ] external/wpt/html/dom/idlharness.https.html?include=(D
 
 # Sheriff 2020-12-14
 crbug.com/1046784 http/tests/devtools/console/console-context-selector.js [ Pass Timeout ]
+
+# Sheriff 2020-12-17
+crbug.com/1043488 [ Win7 ] fast/forms/suggestion-picker/datetimelocal-suggestion-picker-appearance-with-scroll-bar.html [ Pass Failure ]
+crbug.com/1043488 [ Win7 ] fast/forms/suggestion-picker/time-suggestion-picker-appearance-with-scroll-bar.html [ Pass Failure ]
+crbug.com/1043488 [ Win7 ] fast/forms/suggestion-picker/time-suggestion-picker-appearance-locale-hebrew.html [ Pass Failure ]
+crbug.com/1043488 [ Win7 ] fast/forms/suggestion-picker/month-suggestion-picker-appearance-rtl.html [ Pass Failure ]
+crbug.com/1043488 [ Win7 ] fast/forms/suggestion-picker/week-suggestion-picker-appearance-rtl.html [ Pass Failure ]
+crbug.com/1043488 [ Win7 ] fast/forms/suggestion-picker/date-suggestion-picker-appearance-rtl.html [ Pass Failure ]