1577859 - Remove support for container scrolling

Status: RESOLVED FIXED

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

Description

[Botond Ballo [:botond]]

Containerless scrolling has been shipping on Android since 67 (bug 1137890), and on desktop since long before that.

It's been pretty stable and we haven't seen any regressions from it in the past couple of release cycles.

I think this is a good time to remove the container scrolling code. This will make scrolling-related code easier to understand.

Comment 1

[Botond Ballo [:botond]]

Attachment: Bug 1577859 - Remove the layout.scroll.root-frame-containers pref and code that depends directly on it. r=tnikkel

Comment 2

[Botond Ballo [:botond]]

There will be additional cleanup to remove codepaths that were only used with container scrolling but where the dependency is less obvious, but I'm posting what I have for now.

Comment 3

[Botond Ballo [:botond]]

Attachment: Bug 1577859 - Additional post container scrolling removal cleanup in APZ code. r=tnikkel

Depends on D45198

Comment 4

[Botond Ballo [:botond]]

Attachment: Bug 1577859 - Additional post container scrolling removal cleanup in Layout code. r=tnikkel

Depends on D45595

Comment 5

[Botond Ballo [:botond]]

Attachment: Bug 1577859 - Stop handling scrollbar layers that are descendants of the scrolled content. r=tnikkel

With containerless scrolling, scrollbar layers and their target scrolled layers
will be in sibling subtrees.

Depends on D45596

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/286cbc3b542b
Remove the layout.scroll.root-frame-containers pref and code that depends directly on it. r=tnikkel

Comment 7

[Botond Ballo [:botond]]

I'm going to start landing this piece by piece.

Comment 8

[Andrei Ciure[:aciure]]

https://hg.mozilla.org/mozilla-central/rev/286cbc3b542b

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/0ece55dd7147
Additional post container scrolling removal cleanup in Layout code. r=tnikkel

Comment 10

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/0ece55dd7147

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e291531d8dbe
Stop handling scrollbar layers that are descendants of the scrolled content. r=tnikkel
https://hg.mozilla.org/integration/autoland/rev/c0797e496fd9
Additional post container scrolling removal cleanup in APZ code. r=tnikkel

Comment 12

[Stefan Hindli [:stefan_hindli]]

https://hg.mozilla.org/mozilla-central/rev/e291531d8dbe
https://hg.mozilla.org/mozilla-central/rev/c0797e496fd9