1726620 - Add structs representing strong-type app units coordinates

Status: RESOLVED FIXED

(Core :: Layout, enhancement)

Description

[Ting-Yu Lin [:TYLin] (PST, UTC-8)]

The structs are wrappers for int32_t and int64_t representing strong type AppUnit coordinates. I'm planning to use the 64-bit one in flex container to fix bug 1469649.

Comment 1

[Ting-Yu Lin [:TYLin] (PST, UTC-8)]

Attachment: Bug 1726620 Part 1 - Generalize IntCoordTyped template to take a parameter as the underlying type.

This shouldn't change the behavior, but we can use 64-bit T in a later
patch.

Comment 2

[Ting-Yu Lin [:TYLin] (PST, UTC-8)]

Attachment: Bug 1726620 Part 2 - Add structs representing strong-type app units coordinates.

The motivation of introducing the structs is to use 64-bit integer
arithmetic to prevent 32-bit integer overflow. One application is to fix
the integer overflow when resolving flex item's main size in Bug 1469649.

The structs can be a start point to add more useful methods to explore
saturation arithmetic.

Depends on D123265

Comment 3

[Cristina Cozmuta (:CrissCozmuta)]

https://hg.mozilla.org/mozilla-central/rev/25f0f3c961d8
https://hg.mozilla.org/mozilla-central/rev/6a4afc9706c2