1375854 - Don't treat touch-move and touch-end during wheel (or keyboard) scroll animations as unexpected

Status: NEW

(Core :: Panning and Zooming, enhancement, P5)

Description

[Kartikaya Gupta (email:[e-mail])]

One of the comments I made in bug 1351783 comment 132 was this:

> Note to self: there might be a pre-existing bug here, if the user does a wheel 
> scroll (or now a keyboard scroll) while in the middle of a touch-pan gesture. If 
> my reading of the code is correct we'll switch from the TOUCHING or PANNING 
> state to WHEEL_SCROLL (or KEYBOARD_SCROLL) and then if the user moves their 
> finger, we might very well enter here while in that state and hit the 
> NS_WARNING. This might have been impossible before the input block refactoring 
> in bug 1289432 but I should check to see what happens now.

I tested this and indeed, it is now possible to get touch-move and touch-end events during a wheel scroll on Windows touch devices. So we should make sure we don't accidentally print the NS_WARNING at [1] or [2]. They don't get printed in opt builds anyway, and the actual behaviour seems fine so this a super duper low priority bug.

[1] http://searchfox.org/mozilla-central/rev/3291398f10dcbe192fb52e74974b172616c018aa/gfx/layers/apz/src/AsyncPanZoomController.cpp#1148
[2] http://searchfox.org/mozilla-central/rev/3291398f10dcbe192fb52e74974b172616c018aa/gfx/layers/apz/src/AsyncPanZoomController.cpp#1228