crrev.com/c/1277674

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/61701cc0ee389e0dae437516d9b8edad2f874b18

commit 61701cc0ee389e0dae437516d9b8edad2f874b18
Author: Kurt Horimoto <kkhorimoto@chromium.org>
Date: Fri Oct 12 10:24:10 2018

[iOS] Fix BVC's |-isTabScrolledToTopForBubblePresenter:|.

Now that the scroll proxy's contentInset is not guaranteed to be zero,
we need to check against the contentInset instead of CGPointZero.

Bug:  894617 
Cq-Include-Trybots: luci.chromium.try:ios-simulator-cronet;luci.chromium.try:ios-simulator-full-configs
Change-Id: I5ba5131c969a4584879be905a92f0736a34d7f46
Reviewed-on: https://chromium-review.googlesource.com/c/1277674
Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Commit-Queue: Kurt Horimoto <kkhorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599161}
[modify] https://crrev.com/61701cc0ee389e0dae437516d9b8edad2f874b18/ios/chrome/browser/ui/browser_view_controller.mm

I just noticed when looking at the beta-simulator bot that this test fix also needs to be cherry-picked to M71.  PTAL, Kariah!

The bug is marked as P3 or Feature. It should not be merged as M71 is in beta. 
Please contact the approriate milestone owner if you have questions.
Owners: benmason@(Android), kariahda@(iOS), kbleicher@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Assigning to Kariah for review for merge