The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c00a606faa2cd8099f9d88abe08e93c7418fb1fb

commit c00a606faa2cd8099f9d88abe08e93c7418fb1fb
Author: xiyuan <xiyuan@chromium.org>
Date: Wed Aug 31 19:04:31 2016

arc: Fix mouse scroll on notification

Forward ScrollEvent/MouseWheelEvent to the hosting widget so that
it is processed and reaches the containing ScrollView.

Also not forward touch events to ArcCustomNotificationView since
a View is not supposed to receive touch events. This gets rid of
the NOTREACHED() warning in chrome log.

BUG=b/31115616
BUG= 642501 

Review-Url: https://codereview.chromium.org/2291193003
Cr-Commit-Position: refs/heads/master@{#415708}

[modify] https://crrev.com/c00a606faa2cd8099f9d88abe08e93c7418fb1fb/ui/arc/notification/arc_custom_notification_view.cc

Your change meets the bar and is auto-approved for M54 (branch: 2840)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1c40f86a91349db50b862e537694bd6821598f19

commit 1c40f86a91349db50b862e537694bd6821598f19
Author: Xiyuan Xia <xiyuan@google.com>
Date: Thu Sep 01 18:11:39 2016

Merge "arc: Fix mouse scroll on notification"

> Forward ScrollEvent/MouseWheelEvent to the hosting widget so that
> it is processed and reaches the containing ScrollView.
>
> Also not forward touch events to ArcCustomNotificationView since
> a View is not supposed to receive touch events. This gets rid of
> the NOTREACHED() warning in chrome log.
>
> BUG=b/31115616
> BUG= 642501 
>
> Review-Url: https://codereview.chromium.org/2291193003
> Cr-Commit-Position: refs/heads/master@{#415708}
> (cherry picked from commit c00a606faa2cd8099f9d88abe08e93c7418fb1fb)

Review URL: https://codereview.chromium.org/2298213005 .

Cr-Commit-Position: refs/branch-heads/2840@{#99}
Cr-Branched-From: 1ae106dbab4bddd85132d5b75c670794311f4c57-refs/heads/master@{#414607}

[modify] https://crrev.com/1c40f86a91349db50b862e537694bd6821598f19/ui/arc/notification/arc_custom_notification_view.cc

xiyuan@ - Is there any manual test steps available to verify this issue ?
If yes, then please provide the steps to verify it from chrome-Te team.

Repro:
1. Find an app to create notifications (or create your own following https://developer.android.com/training/notify-user/build-notification.html).
2. Bring up the message center after creating 10-20 notifications
3. Try to do a mouse scroll or mouse wheel while the mouse cursor is over an notification

Before the CL, step 3 would be a no-op. After the CL, the notification list should be scrolled.

Retested the issue on windows 10, Ubuntu 14.04 and Mac 10.11.6 using chrome dev version #54.0.2840.14 as per the comment #7 and created custom notifications using google+.
Observed that the notification list is scrollable without any issues.


Attaching a screencast for the same.

xiyuan@ - Could you please check the screencast and confirm if the fix is working.

Deleted: 642501.ogv 3.7 MB

	642501.ogv 3.7 MB View Download

Not sure how OS=all is tagged, but this should be a ChromeOS only and is about the Android app notifications. Web notifications scroll should work without the fix.

8743.35.0 / 54.0.2840.33

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1c40f86a91349db50b862e537694bd6821598f19

commit 1c40f86a91349db50b862e537694bd6821598f19
Author: Xiyuan Xia <xiyuan@google.com>
Date: Thu Sep 01 18:11:39 2016

Merge "arc: Fix mouse scroll on notification"

> Forward ScrollEvent/MouseWheelEvent to the hosting widget so that
> it is processed and reaches the containing ScrollView.
>
> Also not forward touch events to ArcCustomNotificationView since
> a View is not supposed to receive touch events. This gets rid of
> the NOTREACHED() warning in chrome log.
>
> BUG=b/31115616
> BUG= 642501 
>
> Review-Url: https://codereview.chromium.org/2291193003
> Cr-Commit-Position: refs/heads/master@{#415708}
> (cherry picked from commit c00a606faa2cd8099f9d88abe08e93c7418fb1fb)

Review URL: https://codereview.chromium.org/2298213005 .

Cr-Commit-Position: refs/branch-heads/2840@{#99}
Cr-Branched-From: 1ae106dbab4bddd85132d5b75c670794311f4c57-refs/heads/master@{#414607}

[modify] https://crrev.com/1c40f86a91349db50b862e537694bd6821598f19/ui/arc/notification/arc_custom_notification_view.cc