[CrOS Settings] Disable flaky OSSettingsUIBrowserTest browser test

Bug: 1100889
Change-Id: I128da76d5361bfdb24d48108e698b2790ecd5563
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2276522
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Regan Hsu <hsuregan@chromium.org>
Auto-Submit: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Regan Hsu <hsuregan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#784192}

chrome/test/data/webui/settings/chromeos/os_settings_ui_browsertest.js

@@ -41,7 +41,8 @@ var OSSettingsUIBrowserTest = class extends PolymerTest {
   }
 };
 
-TEST_F('OSSettingsUIBrowserTest', 'AllJsTests', () => {
+// TODO(https://crbug.com/1100889): Re-enable flaky test.
+TEST_F('OSSettingsUIBrowserTest', 'DISABLED_AllJsTests', () => {
   suite('os-settings-ui', () => {
     let ui;
     let userActionRecorder;