Reland "Marking SiteSettingsTest.testClearDomainCookies as flaky test."

This reverts commit 4feae4d0.

Reason for revert: this is failing on the official tester on M86, https://crbug.com/1112409#c9

Original change's description:
> Revert "Marking SiteSettingsTest.testClearDomainCookies as flaky test."
> 
> This reverts commit 1d4d72e9.
> 
> Reason for revert: I don't see flakiness on testers for trunk. Maybe the issue got fixed already and only exists in M85.
> 
> Original change's description:
> > Marking SiteSettingsTest.testClearDomainCookies as flaky test.
> > 
> > TBR=dullweber@chromium.org
> > 
> > Bug: 1112409
> > Change-Id: Idf31c4a8d709ddc3f4f87cff63d63881f0198424
> > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2346853
> > Reviewed-by: Ben Mason <benmason@chromium.org>
> > Commit-Queue: Ben Mason <benmason@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#796524}
> 
> TBR=benmason@chromium.org
> 
> Change-Id: Idbbd6d8947bc9d986a16ccd094775e49bd7243d4
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: 1112409
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2348769
> Reviewed-by: Christian Dullweber <dullweber@chromium.org>
> Commit-Queue: Christian Dullweber <dullweber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#796769}

TBR=dullweber@chromium.org,benmason@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1112409
Change-Id: I7a20044bbae961197c6b3354b815bea6c645f238
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2357072Reviewed-by: Nate Fischer <ntfschr@chromium.org>
Commit-Queue: Nate Fischer <ntfschr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#798199}

chrome/android/javatests/src/org/chromium/chrome/browser/site_settings/SiteSettingsTest.java

@@ -30,6 +30,7 @@ import org.chromium.base.test.util.CommandLineFlags;
 import org.chromium.base.test.util.DisableIf;
 import org.chromium.base.test.util.DisabledTest;
 import org.chromium.base.test.util.Feature;
+import org.chromium.base.test.util.FlakyTest;
 import org.chromium.chrome.browser.flags.ChromeSwitches;
 import org.chromium.chrome.browser.notifications.channels.ChromeChannelDefinitions;
 import org.chromium.chrome.browser.notifications.channels.SiteChannelsManager;
@@ -479,6 +480,7 @@ public class SiteSettingsTest {
     @Test
     @SmallTest
     @Feature({"Preferences"})
+    @FlakyTest(message = "https://crbug.com/1112409")
     public void testClearDomainCookies() throws Exception {
         final String url = mPermissionRule.getURLWithHostName(
                 "test.example.com", "/chrome/test/data/android/cookie.html");