Able to reproduce the issue on Win 10 using stable 55.0.2883.87 and canary 57.0.2955.0.
This is regressed in M55.

Bisect info:
=============
Good: 55.0.2875.0
Bad : 55.0.2876.0

Unable to run the Bisect using either new or old script on Windows touch machines.
Omahaproxy UI CL:
https://chromium.googlesource.com/chromium/src/+log/55.0.2875.0..55.0.2876.0?pretty=fuller&n=10000

Possible Suspect from above CL:
Review-Url: https://codereview.chromium.org/2381613003
xidachen@: Could you please take a look into it if its related to your change,else please help assigning to an appropriate owner for this.

Note: Do not have Mac & Linux touch device to verify.

I am very certain the the suspected CL wasn't the cause. I don't have a device to do bisect, but could someone do a bisect and narrow down the range?

Tried re-bisecting the issue and getting Bad revisions only(good:55.0.2872.0).

https://chromium.googlesource.com/chromium/src/+log/55.0.2874.0..55.0.2876.0?pretty=fuller&n=10000

from above CL seeing a touch related change.
related suspect:
Review-Url: https://codereview.chromium.org/2376613002

tsergeant@: Could you please take a look into this if its related to your change, else could you please help finding an appropriate dev person for this.

1. My CL would not have caused this problem, and no other CL in the bisect jumps out as an obvious cause

2. I can't reproduce this issue on a local device. I have a Windows 10 machine with a touch screen and Chrome 55.0.2883.87. Drawing with the touchscreen works fine for me and does not cause the page to scroll.

Just to update regarding the Needs-triage-Mobile label.

Issue is reproducible on the latest stable(55.0.2883.91) and the latest canary(58.0.2993.0) of Nexus-7 Tablet Android Version:5.0.2 Build/LRX22G and HTC 10 Handset Android Version:6.0.1 Build/MMB29M.

Adding the Android label therefore.  

As above, my CL could not have caused this, and nothing else in the existing bisect jumps out.

Unassigning myself and adding Needs-Bisect to try again.

We are able to repro this on Pixel/7.1
Good commit: 421986
Bad commit: 421985
Suspect CL : https://chromium.googlesource.com/chromium/src/+/31637e5d150105f89429c88a651ba1cc4c4453c4

It seems that bisect result is incorrect.

My CL is about presentation API. It has nothing to do with touch screen or drawing. Unassigning myself.

Good build:55.0.2875.0
Bad build: 55.0.2876.0

https://chromium.googlesource.com/chromium/src/+log/55.0.2875.0..55.0.2876.0?pretty=fuller&n=10000

Bisect script pointed to https://chromium.googlesource.com/chromium/src/+/902a3d6303dfbfd49a24173777afcb4b70234a17

Assigning it to relevant owners.

I could repro this issue on Nexus 6 / LMY49C 

The page uses pointer events and doesn't use touch-action
Setting a touch-action: none on the canvas fixes the issue.

This is likely broken on a Microsoft Windows Phone as well. The bisection points to use shipping pointer events.

Does anyone have a contact at the site?

I reached out on twitter to the creator; hopefully this will get resolved in short order. https://twitter.com/dtapuska/status/826204378713321472

Contacted author via email and author applied touch-action. No longer an issue.