Able to reproduce the issue on Windows 7, Ubuntu 14.04 using 52.0.2743.82, latest stable 52.0.2743.116, canary 54.0.2817.0 as per above steps.

This is regression issue broken in M-52.

Please find below bisect info:
Last good build:52.0.2718.0 
First bad build:52.0.2719.0

CHANGELOG URL:
https://chromium.googlesource.com/chromium/src/+log/9c6944d530898d73c02325c0a5c03a257dd7f208..15c6e50b51e8da0393a001a03c50b38f51eb1c01

Unable to find exact suspect from above CL.Hence, marking it as untriaged.
Could anyone from dev team look into this issue and assign it to an appropriate dev person.

Note:Unable to reproduce the issue on Mac 10.11.6.

https://chromium.googlesource.com/chromium/src/+/71cb5b185f274ee0f96b346ce8a515073e9e2975 is suspicious.

Any reason to keep this RVG?

I think none.

@bokan: Gentle Ping.

Could you please provide an update on this issue.

Thank you.

Still looking into it. Should have a fix this week

Any update on the fix as we're getting to M53 Stable promotion?

I have a fix up at https://codereview.chromium.org/2228093003/ but will be away until Aug 18 so likely wont land until then.

M53 Stable launch is coming VERY soon.Your bug is labelled as Stable ReleaseBlock, pls make sure to land the fix asap so it gets chance to bake in beta before stable promotion later this month. Thank you.

 Issue 638671  has been merged into this issue.

Re #11, ok, please request a merge to M53 as soon as change is landed/baked/verified in canary as we're VERY close to M53 stable promotion and this bug is M53 Stable Blocker. Thank you.

Will try to have the fix in ToT by tomorrow EOD.

Please request a merge to M53 as soon as CL is landed/baked/verified in Canary and safe to merge. Thank you.

CL is almost through the CQ: https://codereview.chromium.org/2263503003/ will do once it hits Canary.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/10dc8b7652e6d30337d9bea0ff8bba2592942751

commit 10dc8b7652e6d30337d9bea0ff8bba2592942751
Author: bokan <bokan@chromium.org>
Date: Fri Aug 19 23:45:23 2016

Set WebPagePopupImpl's bounds even if they don't appear to have changed.

In r389984 I tried to make WebPagePopupImpl::resize only call into
setWindowRect (which sends an IPC to the browser process) if the bounds have
actually changed. This uncovered a bug in Aura that was papered up by the fact
that we repeatedly set the bounds. The proper way to fix this is in Aura itself
but we'd like to merge this for release so I'm landing this quick fix to
restore the previous behavior.

I'm working on a proper fix in crrev.com/2228093003

BUG= 633140 

Review-Url: https://codereview.chromium.org/2263503003
Cr-Commit-Position: refs/heads/master@{#413288}

[modify] https://crrev.com/10dc8b7652e6d30337d9bea0ff8bba2592942751/third_party/WebKit/Source/web/WebPagePopupImpl.cpp

I've confirmed the fix in Canary. Requesting merge for 53. The fix should be safe since we're going back to an old behavior and it's very small.

Your change meets the bar and is auto-approved for M53 (branch: 2785)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/09f1017cc167a54a1ed47b7f9aca1ed2bc177eda

commit 09f1017cc167a54a1ed47b7f9aca1ed2bc177eda
Author: David Bokan <bokan@chromium.org>
Date: Mon Aug 22 12:46:42 2016

Set WebPagePopupImpl's bounds even if they don't appear to have changed.

In r389984 I tried to make WebPagePopupImpl::resize only call into
setWindowRect (which sends an IPC to the browser process) if the bounds have
actually changed. This uncovered a bug in Aura that was papered up by the fact
that we repeatedly set the bounds. The proper way to fix this is in Aura itself
but we'd like to merge this for release so I'm landing this quick fix to
restore the previous behavior.

I'm working on a proper fix in crrev.com/2228093003

BUG= 633140 

Review-Url: https://codereview.chromium.org/2263503003
Cr-Commit-Position: refs/heads/master@{#413288}
(cherry picked from commit 10dc8b7652e6d30337d9bea0ff8bba2592942751)

Review URL: https://codereview.chromium.org/2265923002 .

Cr-Commit-Position: refs/branch-heads/2785@{#704}
Cr-Branched-From: 68623971be0cfc492a2cb0427d7f478e7b214c24-refs/heads/master@{#403382}

[modify] https://crrev.com/09f1017cc167a54a1ed47b7f9aca1ed2bc177eda/third_party/WebKit/Source/web/WebPagePopupImpl.cpp

Removing RBS but leaving this open as the fix I landed was a band-aid until I fix this properly.

Tested the issue on Windows 7, Linux Ubuntu 14 using 53.0.2785.80.Observed that popup displayed correctly, it's content wholly visible inside the popup.
Please find attached screencast.

Marking it as TE-Verified.

Deleted: 633140.mp4 698 KB

	633140.mp4 698 KB View Download

@bokan: Could you please change the Status, since this issue is fixed and verified in the comment #23

Ok, I'm still tracking landing a proper fix as I landed a band-aid fix to merge into 53 but I'll open a new bug.