1521278 - Toggling scroll anchoring pref can crash

Status: RESOLVED FIXED

(Core :: Layout: Scrolling and Overflow, enhancement, P3)

Description

[Ryan Hunt [:rhunt]]

We check the scroll-anchoring pref multiple places in ScrollAnchorContainer. The two important ones if we're disabled are that we won't ever select a new anchor, and we won't invalidate an anchor and queue a future selection.

This is a problem because we use Invalidate when a frame is being destroyed to get rid of dangling pointers. We should allow Invalidate to clear frame references without the pref enabled.

Comment 1

[Ryan Hunt [:rhunt]]

Attachment: Bug 1521278 - Allow ScrollAnchorContainer to detach anchor frame even if pref is disabled. r?dholbert

The important piece is just that we don't queue a selection for later. This code runs
for each scroll, so we'd be wasting a lot of effort to do that.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/60944b0fca8f
Allow ScrollAnchorContainer to detach anchor frame even if pref is disabled. r=dholbert

Comment 3

[Razvan Maries]

https://hg.mozilla.org/mozilla-central/rev/60944b0fca8f