This is an omnibox test, not sure if you're the right person to take of care this, please re-assign if necessary.

I'm marking it as RBS just in case this implies a performance degradation, please evaluate.

Issue 798960 has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/97d6d383e64e3a0ad1e570a42ccb2ada497e37ee

commit 97d6d383e64e3a0ad1e570a42ccb2ada497e37ee
Author: Yuke Liao <liaoyuke@chromium.org>
Date: Fri Jan 05 17:22:26 2018

Disable TestTypingInTextField on perf bot.

TestTypingInTextField is extremely flake as it fails more than half of
the runs.

TBR=marq@chromium.org

Bug: 799488
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I5447ada195f65d8f68c44a19939525236851e986
Reviewed-on: https://chromium-review.googlesource.com/852513
Reviewed-by: Yuke Liao <liaoyuke@chromium.org>
Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#527307}
[modify] https://crrev.com/97d6d383e64e3a0ad1e570a42ccb2ada497e37ee/ios/chrome/browser/ui/omnibox_perftest.mm

I looked at this and here's what I found:

The test is supposed to type text in the omnibox and time how long it takes for the
suggestions to appear.
This is achieved by:

1. appending text with setText:
2. waiting for the runloop to spin
3. when the test ends, the runloop is span again, for the typing to "complete"

It seems like after CL 844079 (https://chromium-review.googlesource.com/c/chromium/src/+/844079),
spinning runloop once is not enough for the suggestions to actually start appearing in the popup. 
Only the clipping is resolved after the first runloop spin. This leads the test to believe that 
the characters were typed before they actually change in the textfield. As a result, when the 
test is resetting by calling setText: with an empty string, it doesn't *actually* reset, because 
the characters are still being typed. 

I'll have to investigate a solution for this. 

The good news is that this is a false positive - typing into the omnibox works just fine. 
Hence this should not be RBD. 

Punting this to M-71 as it seems like this will be much easier to fix if we only care about UI Refresh where we don't have clipping.