1318730 - The ScrollInputMethod::MainThreadScrollbarTrackClick telemetry probe misses non-scrollToClick case

Status: RESOLVED FIXED

(Core :: Panning and Zooming, defect, P3)

Description

[Botond Ballo [:botond]]

In bug 1238137 we added telemetry to record different input methods used to scroll.

One of the probes added was for clicking on the scrollbar track (outside of the thumb).

It turns out this can have one of two behaviours, depending on the platform and look-and-feel:

  - The "scroll to click" behaviour, where we scroll all the way to the point
    where the thumb is under the mouse.

  - A behaviour where we just scroll by one page in that direction.

At the time I wrote the probe, I was only aware of the "scroll to click" behaviour, and only instrumented that one (the two behaviours take different codepaths).

In this bug, I'd like to adjust the probe to cover the non-scrollToClick case as well.

Thanks Ryan for spotting this!

Comment 1

[Botond Ballo [:botond]]

Attachment: Bug 1318730 - Fire the ScrollInputMethod::MainThreadScrollbarTrackClick telemetry probe in the non-scrollToClick case as well.

Review commit: https://reviewboard.mozilla.org/r/94070/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/94070/

Comment 2

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

Comment on attachment 8812255 [details]
Bug 1318730 - Fire the ScrollInputMethod::MainThreadScrollbarTrackClick telemetry probe in the non-scrollToClick case as well.

https://reviewboard.mozilla.org/r/94070/#review94234

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/0fc9b3fb2d5d
Fire the ScrollInputMethod::MainThreadScrollbarTrackClick telemetry probe in the non-scrollToClick case as well. r=kats

Comment 4

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/0fc9b3fb2d5d