based on offline chat with Isha this is specific to Android hence tagging the bug as Android.

Please provide a sample testcase/url device deatils for further investigation.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6dd5a34b1d4fd761152d93e251546cd84730187b

commit 6dd5a34b1d4fd761152d93e251546cd84730187b
Author: Isha Bobra <ibobra@google.com>
Date: Tue Sep 12 18:31:01 2017

Android Accessibility: fix return value for scroll actions

There is a chance that a race condition occurs where the page returns canScrollForward/backward/up/down/left/right as true but actually the page cannot scroll further.
In those cases the scroll function in browser android accessibility should return false instead of
true.

Bug:  763014 
Change-Id: I777b5fb562713e0bd835a354adab9cbf86fcd853
Reviewed-on: https://chromium-review.googlesource.com/661718
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#501340}
[modify] https://crrev.com/6dd5a34b1d4fd761152d93e251546cd84730187b/content/browser/accessibility/browser_accessibility_android.cc

@ibobra -- Could you please provide any sample testcase/url as per Comment# 2 which would help us in triaging the issue further.
Thanks in Advance.

I have already landed a fix for this issue. This bug can be closed and no triage is required :)