[Sheriff] Disable flaky CrElementsDrawerTest.Drawer on Mac

TBR=rbpotter@chromium.org

Bug: 1096016
Change-Id: I7d1fabccb14f55756e7e279938337fd44bf2e0a1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2248684Reviewed-by: Ioana Pandele <ioanap@chromium.org>
Commit-Queue: Ioana Pandele <ioanap@chromium.org>
Cr-Commit-Position: refs/heads/master@{#779303}

chrome/test/data/webui/cr_elements/cr_elements_browsertest.js

@@ -124,7 +124,13 @@ CrElementsDrawerTest.prototype = {
   ]),
 };
 
-TEST_F('CrElementsDrawerTest', 'Drawer', function() {
+// https://crbug.com/1096016 - flaky on Mac
+GEN('#if defined(OS_MACOSX)');
+GEN('#define MAYBE_Drawer DISABLED_Drawer');
+GEN('#else');
+GEN('#define MAYBE_Drawer Drawer');
+GEN('#endif');
+TEST_F('CrElementsDrawerTest', 'MAYBE_Drawer', function() {
   mocha.run();
 });