1143665 - Remove the scroll position passed around in the scrollview event

Status: RESOLVED FIXED

(Core :: Panning and Zooming, defect)

Description

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

See bug 1142926 comment 4 and bug 1142926 comment 7. The scrollview event dispatched starting at [1] includes a scroll position x,y which is nonsensical because it doesn't specify which scrollframe is being scrolled. Without this information the scroll position cannot possibly be interpreted in a sensical manner, leading to a footgun if anybody tries to use these values. Since the values are not being used anymore we should just remove them.

[1] mxr.mozilla.org/mozilla-central/source/gfx/layers/apz/util/APZEventState.cpp?rev=f9b76a07fcc6#327

Comment 1

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

Attachment: Gecko patch

This rips out the stuff on the gecko side. I noticed that in gaia/tv_apps/smart-system/js/text_selection_dialog.js there is still some code that uses the x and y scroll offsets - does that code need updating? It looks like a fork of gaia/apps/system/js/text_selection_dialog.js that is out of date.

Comment 2

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Comment on attachment 8580915 [details] [diff] [review]
Gecko patch

Review of attachment 8580915 [details] [diff] [review]:
-----------------------------------------------------------------

This patch looks good to me.

Comment 3

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

I don't know how gaia/tv_apps/smart-system/js/text_selection_dialog.js is being used.

George, John, need your feedback about comment 1.

Comment 4

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Comment on attachment 8580915 [details] [diff] [review]
Gecko patch

Review of attachment 8580915 [details] [diff] [review]:
-----------------------------------------------------------------

Kats, your probably forgot to add those changes to SelectionCarets.h in this patch.

Comment 5

[Morris Tseng [:mtseng] [:Morris] (Inactive)]

Comment on attachment 8580915 [details] [diff] [review]
Gecko patch

LGTM.

Comment 6

[John Hu [:johnhu][:johu][:醬糊小弟]]

We may not need it in smart-system. I will make a patch to remove that from smart-system.

Comment 7

[John Hu [:johnhu][:johu][:醬糊小弟]]

BTW, we are going to merge smart system back to system app.

Comment 8

[(Inactive after June) George Duan [:gduan] [:喬智]]

TextSelectionDialog doesn't need value of scrollX and scrollY.

Comment 9

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

Attachment: Remove scroll position from scrollviewchange event

Fixed up the header and another call site - not sure why I didn't catch those before. Based on the fact that the scroll position isn't used anywhere (the only use site will be removed as per comment 6) I think this should be safe to land now.

Comment 10

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

Comment on attachment 8582391 [details] [diff] [review]
Remove scroll position from scrollviewchange event

Hm, the prevent_webidl_changes.py hg hook tells me I can't land this without DOM peer review because it touches a .webidl file.

Comment 11

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

Thanks!

https://hg.mozilla.org/integration/mozilla-inbound/rev/584132a97872

Comment 12

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/584132a97872