1825411 - [CTW] Scroll regions with scroll offset (0,0) do not have cached scroll position

Status: RESOLVED FIXED

(Core :: Disability Access APIs, defect)

Description

[Nathan LaPré]

In a document with a scroll region that's not scrolled, the accessible for the scroll region will have no cached scroll position, making it impossible to tell whether we're actually dealing with a scroll region in RemoteAccessibleBase. This is because of this code in BundleFieldsForCache which avoids caching scroll positions when the position is (0,0), even if we are dealing with a scroll region.

We might be able to use the scrollRange variable to indicate whether there's a scroll region. If there is, we should send a scroll position, even if it's (0,0), so that we can use the presence/absence of a scroll position as an indicator that a scroll region exists for a given Accessible in RemoteAccessible (see RemoteAccessibleBase::ApplyScrollOffset).

We should also be careful to ensure that we're removing the scroll position from the cache if the Accessible becomes unscrollable for some reason.

Comment 1

[Morgan Reschenberg [:morgan]]

Attachment: Bug 1825411: Cache scroll position for unscrolled scroll frames r?nlapre,Jamie

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/fa9772a45927
Cache scroll position for unscrolled scroll frames r=nlapre

Comment 3

[Natalia Csoregi [:nataliaCs]]

Backed out with Bug 1828373 and Bug 1825611 for accessible failures on on /browser_general.js

• backout: https://hg.mozilla.org/integration/autoland/rev/8d8d99e7581851de698e27339dffd60ee8dc8e32

Comment 4

[Norisz Fay [:noriszfay]]

Backout merged to central: https://hg.mozilla.org/mozilla-central/rev/8d8d99e75818

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a765e16b163a
Cache scroll position for unscrolled scroll frames r=nlapre

Comment 6

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/a765e16b163a