The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b81d3e2e3e2c455e5199c568b71df84a34d56a81

commit b81d3e2e3e2c455e5199c568b71df84a34d56a81
Author: Menglu Huang <huangml@chromium.org>
Date: Fri Feb 23 04:53:33 2018

Mark some SyncFakeServerTestCase tests as flaky for simulators.

Bug:  814990 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I0a456123b9e475b8175db026075bcfcabc5bdf77
Reviewed-on: https://chromium-review.googlesource.com/933114
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Commit-Queue: Menglu Huang <huangml@chromium.org>
Cr-Commit-Position: refs/heads/master@{#538704}
[modify] https://crrev.com/b81d3e2e3e2c455e5199c568b71df84a34d56a81/ios/chrome/browser/ui/settings/sync_utils/sync_fake_server_egtest.mm

These are also failing on devices. I will need to disable them on devices as well. 

https://chromium-review.googlesource.com/c/chromium/src/+/960842
Disabled tests on devices.

These tests have been failing on these device bots:
(iPad Air iOS 10.3.3) on iOS-10.3.3
(iPhone 6s iOS 10.3.3) on iOS-10.3.3

Since March 7, revision:
1cbfed836fceb54df561b43e7cd8e5d65ea41137

Created a separate bug for device flakiness. 
https://bugs.chromium.org/p/chromium/issues/detail?id=821490

Now the multiple simulator mode is off for these tests.  They shouldn't be failing due to that. 
Blocked on issue 821490 to re-enable these tests.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a7015304094dc5ee1d90d856e024acf0ba53dbe1

commit a7015304094dc5ee1d90d856e024acf0ba53dbe1
Author: Menglu Huang <huangml@chromium.org>
Date: Thu Mar 15 23:24:16 2018

Re-disable SyncFakeServer tests on simulators and change bug number.

These tests were disabled for simulators for being flaky under multiple
simulators mode. Now the mode is turned off for these tests, they should
be re-enabled again,  but still failing due to issue 821490.

Bug:  814990 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: Ie75bfa9ed9ba14552123199ff2d202477ae12457
Reviewed-on: https://chromium-review.googlesource.com/961595
Commit-Queue: Menglu Huang <huangml@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543543}
[modify] https://crrev.com/a7015304094dc5ee1d90d856e024acf0ba53dbe1/ios/chrome/browser/ui/settings/sync_utils/sync_fake_server_egtest.mm

Just failed on the simulator. Should it be disabled?

https://logs.chromium.org/v/?s=chromium%2Fbb%2Fchromium.mac%2Fios-simulator%2F31531%2F%2B%2Frecipes%2Fsteps%2Fios_chrome_ui_egtests__iPhone_6s_iOS_11.2__shard_2%2F0%2Flogs%2FSyncFakeServerTestCase__x2f_testSyncCheckSameCacheGuid_SyncRestartedAfterSignOutAndSignIn%2F0

SyncFakeServerTestCase/testSyncCheckSameCacheGuid_SyncRestartedAfterSignOutAndSignIn:
[0410/013249.206932:WARNING:syncer_proto_util.cc(338)] Error posting from syncer: Response Code (bogus on error): -1 Content-Length (bogus on error): -1 Server Status: SYNC_AUTH_ERROR
[0410/013249.221710:WARNING:get_updates_processor.cc(103)] Skipping unexpected progress marker for non-enabled type Bookmarks
[0410/013249.221884:ERROR:account_tracker.cc(296)] OnOAuthError
[0410/013249.222035:WARNING:account_tracker.cc(216)] Failed to get UserInfo for foo1ID
[0410/013249.222372:WARNING:sync_encryption_handler_impl.cc(970)] Nigori had empty encryption keybag.
[0410/013249.223910:WARNING:sync_encryption_handler_impl.cc(970)] Nigori had empty encryption keybag.
[0410/013251.436884:WARNING:get_updates_processor.cc(103)] Skipping unexpected progress marker for non-enabled type Bookmarks
[0410/013253.054643:INFO:signin_manager.cc(249)] Revoking all refresh tokens on server. Reason: sign out, IsSigninAllowed: 1
../../ios/chrome/test/earl_grey/chrome_earl_grey_ui.mm:73: error: -[SyncFakeServerTestCase testSyncCheckSameCacheGuid_SyncRestartedAfterSignOutAndSignIn] : Exception: NoMatchingElementException
Exception Name: NoMatchingElementException
Exception Reason: Cannot find UI element.
Exception with Action: {
  "Action Name" : "Tap",
  "Element Matcher" : "((respondsToSelector(accessibilityIdentifier) && accessibilityID('kToolsMenuSettingsId')) && interactable)",
  "Recovery Suggestion" : "Check if the element exists in the UI hierarchy printed below. If it exists, adjust the matcher so that it accurately matches element."
}

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/74b8a83cfcdde1045b3bfeed81a52f50081b0f2c

commit 74b8a83cfcdde1045b3bfeed81a52f50081b0f2c
Author: Vasilii Sukhanov <vasilii@chromium.org>
Date: Tue Apr 10 11:47:28 2018

Disable 2 flaky SyncFakeServerTestCase tests on iOS.

TBR=huangml@chromium.org

Bug:  814990 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I6db1b62ec0b0d007fdcde56b866ce6500ec71234
Reviewed-on: https://chromium-review.googlesource.com/1005078
Commit-Queue: Vasilii Sukhanov <vasilii@chromium.org>
Reviewed-by: Vasilii Sukhanov <vasilii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549490}
[modify] https://crrev.com/74b8a83cfcdde1045b3bfeed81a52f50081b0f2c/ios/chrome/browser/ui/settings/sync_utils/sync_fake_server_egtest.mm

The tests are not failing due to sharding.  Should be issue 821490