1638655 - Perfherder test-suite drop down is broken on mobile

Status: RESOLVED FIXED

(Core :: Panning and Zooming, defect, P2)

Description

[Ted Campbell [:tcampbell]]

On Fenix/GeckoViewExample on mobile.

STR:

• Visit https://treeherder.mozilla.org/perf.html#/comparechooser?newProject=mozilla-central&newRevision=5f7897d4523021ee64a2d75eb9ace78bdd8d6133
• Pinch-zoom (I do roughly 2x)
• Tap talos to get test-suite drop down
• Tap awsy from the list

Expected:

• Selection changes to awsy

Actual:

• Selection unchanged, and drop-down is dismissed.

I used geckoview-example ARM64 PGO builds from mozilla-central to confirm.
Last working: https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&revision=385f49adaf00d02fc8e04da1e0031e3477182d67
Regressed by: https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&revision=1fa1d4f4b0e247804927d474cfecdf6c6f185203
Still broken at: https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&revision=5f7897d4523021ee64a2d75eb9ace78bdd8d6133

Comment 1

[Botond Ballo [:botond]]

Thanks for the report, I can reproduce.

Comment 3

[Botond Ballo [:botond]]

This is an issue with doing main-thread hit testing in layout coordinates (nsDisplayListBuilder::IsRelativeToLayoutViewport() == true).

In such scenarios, the point being hit tested is in layout coordinates, and we do not build an async zoom container or ever apply a visual-to-layout transform to the point. However, we clip the RCD-RSF's scrolled content to a "composition bounds clip".

The intent of this clip is to restrict the area being hit-tested to the visual viewport (composition bounds). Since we're hit-testing in layout coordinates, this should therefore be the visual viewport in layout coordinates.

The rect we're currently using, with the offset from mScrollPort and the size being CalculateCompositionSizeForFrame(), is essentially the visual viewport in visual coordinates. To get it to be in layout coordinates, we divide it by the resolution, but we need to also translate it by the offset of the visual viewport relative to the layout viewport.

Comment 4

[Botond Ballo [:botond]]

Attachment: Bug 1638655 - When hit testing in layout coordinates, transform the composition bounds clip to layout coordinates. r=tnikkel

Previously, we were only performing part of this transform
(scaling by the resolution) and not the other part
(translating by the offset between the two viewports).

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/316df381b64b
When hit testing in layout coordinates, transform the composition bounds clip to layout coordinates. r=tnikkel

Comment 7

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/316df381b64b