Weirdly,

* The zoom icon has an active state when you open the bubble by clicking the icon; but it doesn't when the bubble appears because you hit ctrl-+/-.  (This is also true of the bookmark star, maybe it's true of all omnibox icons?)
* Similarly, the bubble has an anchor arrow in the latter case, but not the former

The anchor arrows are all going away in Harmony, so I'd be OK with killing them all now if we get active states to replace them in all cases.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d7887d9cb29d090b72fbecc5b260ae68b09ce27e

commit d7887d9cb29d090b72fbecc5b260ae68b09ce27e
Author: spqchan <spqchan@chromium.org>
Date: Thu Jun 08 20:25:00 2017

[Mac] Active States for the Omnibox Zoom Icon

On Mac, Page Zoom via Cmd +/- currently doesn't highlight
the omnibox zoom icon (for both Views and Cocoa dialogs).

This change highlights the icon when the dialog is visible.

Bug:  725806 
Change-Id: I38dab4ea43628fc040e431181b989c96c97fa6f2
Reviewed-on: https://chromium-review.googlesource.com/522925
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Commit-Queue: Sarah Chan <spqchan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#478070}
[modify] https://crrev.com/d7887d9cb29d090b72fbecc5b260ae68b09ce27e/chrome/browser/ui/browser_dialogs.h
[modify] https://crrev.com/d7887d9cb29d090b72fbecc5b260ae68b09ce27e/chrome/browser/ui/cocoa/browser/zoom_bubble_controller.h
[modify] https://crrev.com/d7887d9cb29d090b72fbecc5b260ae68b09ce27e/chrome/browser/ui/cocoa/browser/zoom_bubble_controller.mm
[modify] https://crrev.com/d7887d9cb29d090b72fbecc5b260ae68b09ce27e/chrome/browser/ui/cocoa/browser_dialogs_views_mac.cc
[modify] https://crrev.com/d7887d9cb29d090b72fbecc5b260ae68b09ce27e/chrome/browser/ui/cocoa/browser_dialogs_views_mac.h
[modify] https://crrev.com/d7887d9cb29d090b72fbecc5b260ae68b09ce27e/chrome/browser/ui/cocoa/location_bar/location_bar_view_mac.h
[modify] https://crrev.com/d7887d9cb29d090b72fbecc5b260ae68b09ce27e/chrome/browser/ui/cocoa/location_bar/zoom_decoration.mm

Whoops, the CL has the wrong bug on it. It should fix  Issue 725566 . Please disregard it

Looks like this got fixed