[Sheriff]: Disable flaky TestUnsafeContentsInWorkerWithUserException.

The test
SSLUIWorkerFetchTest.TestUnsafeContentsInWorkerWithUserException is
flaky. Disable it.

BUG=1107659
TBR=estark@chromium.org

Change-Id: I448295f1e04e14170cc494c4e39170eb4f745b66
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2309039
Commit-Queue: Karan Bhatia <karandeepb@chromium.org>
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#790207}

chrome/browser/ssl/ssl_browsertest.cc

@@ -3607,8 +3607,9 @@ IN_PROC_BROWSER_TEST_P(SSLUIWorkerFetchTest,
 // This test, and the related test TestUnsafeContentsWithUserException, verify
 // that if unsafe content is loaded but the host of that unsafe content has a
 // user exception, the content runs and the security style is downgraded.
+// TODO(crbug.com/1107659): Disabled due to flakiness.
 IN_PROC_BROWSER_TEST_P(SSLUIWorkerFetchTest,
-                       TestUnsafeContentsInWorkerWithUserException) {
+                       DISABLED_TestUnsafeContentsInWorkerWithUserException) {
   https_server_.ServeFilesFromDirectory(tmp_dir_.GetPath());
   https_server_mismatched_.ServeFilesFromDirectory(tmp_dir_.GetPath());
   ASSERT_TRUE(https_server_.Start());