Indeed, this is probably something we have introduced during the refactoring as it is also happening on M65.
However having no progress indicator at all on iPad feels weird. Maybe we should let it?
+mardini for opinion.

We have no determinate progress indicator on desktop and that's what this UI is intended to mimic. 

+ainslie for comment (though he's on vacation). 

I'll defer to +edwardjung@ who has been doing some work in this space recently (for Desktop). In general, keeping our progress indication UIs in the tabstrip consistent across touch and non-touch sounds right. 

https://groups.google.com/a/google.com/d/msg/chrome-ui-review/M8m_6QFOqAk/NgXDLzr_AAAJ

We're looking to replace the indeterminate spinner with a two part:
- indeterminate for the connection phase
- determinate loader when loading happens.

There's a bug open for it with a link the proposal and a prototype (https://bugs.chromium.org/p/chromium/issues/detail?id=695714#c17) and it's been through UI review (per the link in #5). 

I've not done much work on iOS so don't know if this change would work for the iPad UI.

Thanks, Edward. I guess this is not implemented on desktop yet, right? For the time being, we'll fix the bug on iPad (by going back to how we were, no progress bar) 

That's right it's not implemented yet. Awaiting eng resources to become available.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/7b0606106adea5683a4b47fa5c6c3b1d3cb1486b

commit 7b0606106adea5683a4b47fa5c6c3b1d3cb1486b
Author: Gauthier Ambard <gambard@chromium.org>
Date: Wed Feb 28 14:32:33 2018

Don't show the progress bar on iPad

This CL doesn't show the progress bar during the loading of the page on
iPad.

Bug:  813073 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I94c2ca6b28906220aeaf7affca702bd36e49b0d8
Reviewed-on: https://chromium-review.googlesource.com/941223
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539820}
[modify] https://crrev.com/7b0606106adea5683a4b47fa5c6c3b1d3cb1486b/ios/chrome/browser/ui/toolbar/clean/toolbar_view_controller.mm

Verified in:

App Version: 67.0.3363.0 canary
Devices: iPad Air, iPad Mini
iOS Versions: 11.2.6, 11.3 beta 4

Progress bar is not shown when the page is loading in iPads.

Video:
https://drive.google.com/open?id=1cp6tCUeD3v_ssVWC5YN6dZkUupT-VjVn