Bug in steps (4)-(6) should be solved by https://codereview.chromium.org/2336983002/. 

Bug in steps (1)-(3) seems to be caused by the Slide Animation with which the Find-In-Page popup is shown.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e5cbef5ab4cea989839c24925113f5a062a2fb9a

commit e5cbef5ab4cea989839c24925113f5a062a2fb9a
Author: karandeepb <karandeepb@chromium.org>
Date: Thu Sep 15 08:06:07 2016

MacViews: Trigger shadow invalidation when a translucent window is shown.

Currently, invalidate_shadow_on_frame_swap_ is not set when a MacViews window is
shown. It is only set when the layer is created, changed or the window resized.
This causes translucent windows like the "Restore Pages" bubble and Find-In-Page
window to not have a shadow, when they are shown after being hidden.

This CL modifies BridgedNativeWidget::OnVisibilityChanged() to trigger shadow
invalidation while showing translucent windows. This fixes the shadow for the
"Restore Pages" bubble and also of the Find-In-Page window on tab switching. A
unit test is also added which demonstrates the problem.

Note that this does not fix the shadow for the Find-In-Page window when it is
displayed initially on pressing Cmd+F.

BUG= 636707 ,  646734 

Review-Url: https://codereview.chromium.org/2336983002
Cr-Commit-Position: refs/heads/master@{#418803}

[modify] https://crrev.com/e5cbef5ab4cea989839c24925113f5a062a2fb9a/ui/views/cocoa/bridged_native_widget.mm
[modify] https://crrev.com/e5cbef5ab4cea989839c24925113f5a062a2fb9a/ui/views/widget/native_widget_mac_unittest.mm

karandeepb@: Was the fix landed in 2336983002 complete, or is there more to this?

Don't think this was fixed. The fix should have solved the bug in steps (4)-(6). See c#1 and c#2.

lgrey, can you take a peek at this please? :)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/50302927e77c1b3033af0e1b584abbcf4488866f

commit 50302927e77c1b3033af0e1b584abbcf4488866f
Author: Leonard Grey <lgrey@chromium.org>
Date: Thu Oct 26 16:21:49 2017

[MacViews] Move FindBar to views shadows

Currently, Views shadows are not drawn on Mac. Instead, the macOS Window Server
draws shadows based on the contents of the window.

This can cause issues when the window's contents are animated in through a
views animation. The window has no way of knowing that the contents have
changed, so it doesn't invalidate its shadow, causing glitches like missing
or partial shadows.

This change restores views shadows on Mac and introduces a new (synthetic)
option to the Shadow enum: DIALOG_SHADOW which disables views shadows on
Mac and renders as SMALL_SHADOW otherwise. DIALOG_SHADOW should be used
in cases where a window can move or overlap the browser window in order
to fall back to the window server.

Bug:  646734 
Change-Id: I5d24a27f0d0455c70c235c91b5580364be7e11e5
Reviewed-on: https://chromium-review.googlesource.com/735754
Commit-Queue: Leonard Grey <lgrey@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511840}
[modify] https://crrev.com/50302927e77c1b3033af0e1b584abbcf4488866f/ui/views/bubble/bubble_border.cc
[modify] https://crrev.com/50302927e77c1b3033af0e1b584abbcf4488866f/ui/views/bubble/bubble_border.h
[modify] https://crrev.com/50302927e77c1b3033af0e1b584abbcf4488866f/ui/views/bubble/bubble_border_unittest.cc
[modify] https://crrev.com/50302927e77c1b3033af0e1b584abbcf4488866f/ui/views/bubble/bubble_dialog_delegate.cc
[modify] https://crrev.com/50302927e77c1b3033af0e1b584abbcf4488866f/ui/views/cocoa/bridged_native_widget.mm
[modify] https://crrev.com/50302927e77c1b3033af0e1b584abbcf4488866f/ui/views/window/dialog_delegate.cc