Verified, also on 70.0.3516.0 canary. I'm on Windows. 

Marking available but tentatively setting owner to tommycli - in case a fix and merge is needed for M69.

as suggested by step (2), verified it also repros on other SearchEngines like amazon.com - that's expected given it repros on youtube, but just mentioning for completeness :). 

Tentatively M69 but not sure on the blocking-ness.

Travis, thanks for reproing.

M-69 seems appropriate if we can come up with a one-line fix.

Let me take a look.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/af3a6bdc31c29746d749ba0ab9e7181c49c11642

commit af3a6bdc31c29746d749ba0ab9e7181c49c11642
Author: Tommy C. Li <tommycli@chromium.org>
Date: Thu Aug 09 16:44:11 2018

Omnibox Refresh UI: Hide placeholder text when keyword is selected

Previously, when a keyword was selected, i.e. "Search Yahoo", we would
still show the placeholder text in the Omnibox when unfocused, like:
"Search Google or enter a URL".

That is plainly not applicable to the selected keyword case. We don't
need to show placeholder text at all when there is a selected keyword,
since the selected keyword label itself gives ample instruction to the
user.

Bug:  872327 
Change-Id: I84fd06964808554e5c606d2f2f371bea9c44b465
Reviewed-on: https://chromium-review.googlesource.com/1168506
Reviewed-by: Kevin Bailey <krb@chromium.org>

[modify] https://crrev.com/af3a6bdc31c29746d749ba0ab9e7181c49c11642/chrome/browser/ui/views/omnibox/omnibox_view_views.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/23b998cb1f5ce77f7143a4b6bc96f2f13bf973e4

commit 23b998cb1f5ce77f7143a4b6bc96f2f13bf973e4
Author: Andrii Shyshkalov <tandrii@chromium.org>
Date: Thu Aug 09 19:09:29 2018

Revert "Omnibox Refresh UI: Hide placeholder text when keyword is selected"

This reverts commit af3a6bdc31c29746d749ba0ab9e7181c49c11642.

Reason for revert: Due to Gerrit outage  http://crbug.com/872722 , we are reverting this CL. Please, re-land it after all clear is given. If you have questions, please ask on the bug. Sorry for the inconvenience.

Original change's description:
> Omnibox Refresh UI: Hide placeholder text when keyword is selected
> 
> Previously, when a keyword was selected, i.e. "Search Yahoo", we would
> still show the placeholder text in the Omnibox when unfocused, like:
> "Search Google or enter a URL".
> 
> That is plainly not applicable to the selected keyword case. We don't
> need to show placeholder text at all when there is a selected keyword,
> since the selected keyword label itself gives ample instruction to the
> user.
> 
> Bug:  872327 
> Change-Id: I84fd06964808554e5c606d2f2f371bea9c44b465
> Reviewed-on: https://chromium-review.googlesource.com/1168506
> Reviewed-by: Kevin Bailey <krb@chromium.org>

TBR=krb@chromium.org,tommycli@chromium.org

Change-Id: Ibbc17b665c1e4be7f167de40d39a584f867f7f2b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug:  872327 
Reviewed-on: https://chromium-review.googlesource.com/1169842
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>

[modify] https://crrev.com/23b998cb1f5ce77f7143a4b6bc96f2f13bf973e4/chrome/browser/ui/views/omnibox/omnibox_view_views.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/25019a6468a5e76a84ccf0e7a749a3616105af0e

commit 25019a6468a5e76a84ccf0e7a749a3616105af0e
Author: Tommy C. Li <tommycli@chromium.org>
Date: Fri Aug 10 00:31:56 2018

Reland "Omnibox Refresh UI: Hide placeholder text when keyword is selected"

This is a reland of af3a6bdc31c29746d749ba0ab9e7181c49c11642

Original change's description:
> Omnibox Refresh UI: Hide placeholder text when keyword is selected
>
> Previously, when a keyword was selected, i.e. "Search Yahoo", we would
> still show the placeholder text in the Omnibox when unfocused, like:
> "Search Google or enter a URL".
>
> That is plainly not applicable to the selected keyword case. We don't
> need to show placeholder text at all when there is a selected keyword,
> since the selected keyword label itself gives ample instruction to the
> user.
>
> Bug:  872327 
> Change-Id: I84fd06964808554e5c606d2f2f371bea9c44b465
> Reviewed-on: https://chromium-review.googlesource.com/1168506
> Reviewed-by: Kevin Bailey <krb@chromium.org>

TBR=krb@chromium.org

Bug:  872327 
Change-Id: I978f264d1d37b883e6e75b460b923573b01ada61
Reviewed-on: https://chromium-review.googlesource.com/1169931
Commit-Queue: Tommy Li <tommycli@chromium.org>
Reviewed-by: Tommy Li <tommycli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581983}
[modify] https://crrev.com/25019a6468a5e76a84ccf0e7a749a3616105af0e/chrome/browser/ui/views/omnibox/omnibox_view_views.cc

I just verified in Canary. Requesting a merge to 69.

It's a one-line fix with low technical risk that makes a user visible improvement.

Approving merge for CL listed at #8 to M69 branch 3497 based on comment #9. Please merge ASAP. Thank you.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4f7bf86c961674495271dca478e5d85268b8b9ad

commit 4f7bf86c961674495271dca478e5d85268b8b9ad
Author: Tommy C. Li <tommycli@chromium.org>
Date: Fri Aug 10 18:20:44 2018

Reland "Omnibox Refresh UI: Hide placeholder text when keyword is selected"

This is a reland of af3a6bdc31c29746d749ba0ab9e7181c49c11642

Original change's description:
> Omnibox Refresh UI: Hide placeholder text when keyword is selected
>
> Previously, when a keyword was selected, i.e. "Search Yahoo", we would
> still show the placeholder text in the Omnibox when unfocused, like:
> "Search Google or enter a URL".
>
> That is plainly not applicable to the selected keyword case. We don't
> need to show placeholder text at all when there is a selected keyword,
> since the selected keyword label itself gives ample instruction to the
> user.
>
> Bug:  872327 
> Change-Id: I84fd06964808554e5c606d2f2f371bea9c44b465
> Reviewed-on: https://chromium-review.googlesource.com/1168506
> Reviewed-by: Kevin Bailey <krb@chromium.org>

TBR=krb@chromium.org

Bug:  872327 
Change-Id: I978f264d1d37b883e6e75b460b923573b01ada61
Reviewed-on: https://chromium-review.googlesource.com/1169931
Commit-Queue: Tommy Li <tommycli@chromium.org>
Reviewed-by: Tommy Li <tommycli@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#581983}(cherry picked from commit 25019a6468a5e76a84ccf0e7a749a3616105af0e)
Reviewed-on: https://chromium-review.googlesource.com/1171262
Cr-Commit-Position: refs/branch-heads/3497@{#539}
Cr-Branched-From: 271eaf50594eb818c9295dc78d364aea18c82ea8-refs/heads/master@{#576753}
[modify] https://crrev.com/4f7bf86c961674495271dca478e5d85268b8b9ad/chrome/browser/ui/views/omnibox/omnibox_view_views.cc

Looks great. Thank you, Tommy :)

+abdulsyed@ fyi, M69 merges taken for Proj-MdRefresh .

Tried testing the issue on Win-10 using chrome reported version #70.0.3516.0.
Attached a screen cast for reference.

Note: Enabled #upcoming-ui-features before following the steps to reproduce.
Following are the steps followed to reproduce the issue.
------------
(1) Typed youtube.com into the Omnibox
(2) Pressed Tab-Key and observed that the SearchEngine Search did not appear.

tommycli@ - Could you please check the attached screen cast and please let us know if any thing missed from our end in verifying the fix.

Thanks...!!

Deleted: 872327.mp4 1.0 MB

	872327.mp4 1.0 MB View Download

See https://bugs.chromium.org/p/chromium/issues/detail?id=871265#c18 for a response on reproducing.

Try using yahoo.com instead.

Thank you Tommy, Verified the fix on latest Chrome 69.0.3497.42 on Windows, Mac and Linux with steps below :

Pre-requisite : Enabled #upcoming-ui-features from chrome://flags

Steps to reproduce :
1. Launch Chrome and enable above specified flag from Chrome://flags
2. Visit any webpage or just about://version
3. With in same tab type in youtube.com or yahoo.com and Press Tab-Key, so that the SearchEngine Search appears
4. Click outside the Chrome window (e.g. Desktop)

Observed behavior :
There isn't "Search Google or type a URL" text in Omnibox.