Bugzilla

After this patch, there are a lot of build errors since now int32_t and
nscoord is not the same type anymore.

BaseCoord can convert to int32_t automatically, but not at the follow cases.

1. Calling std::min(0, nscoord) or std::max(0, nscoord). We'll need to
explicit create nscoord(0) instead of using 0, or calling
std::min<nscoord>() or std::max<nscoord>().

2. Ternary operator like `condition ? nscoord : 0`. Need a manually fix
by `condition ? nscoord : nscoord(0)`.

3. The gecko interface between servo Au.

For code like `Size2D::new(Au(area.width), Au(area.height))` [1], should
we sprinkle nscoord's `value` member and use it like `area.width.value`?
Or can we convert Au to nscoord automatically? I haven't figure this out
yet.

[1] https://searchfox.org/mozilla-central/rev/2c1092dc68c63f7bad6da6a03c5883a5ab5ff2ca/servo/components/style/gecko/media_features.rs#26

After this patch, there are a lot of build errors since now int32_t and
nscoord is not the same type anymore.

`BaseCoord` can convert to `int32_t` automatically, but not at the following cases.

1. Calling `std::min(0, nscoord)` or `std::max(0, nscoord)`. We'll need to
explicit create `nscoord(0)` instead of using 0, or calling
`std::min<nscoord>()` or `std::max<nscoord>()`.

2. Ternary operator like `condition ? nscoord : 0`. Need a manually fix
by `condition ? nscoord : nscoord(0)`.

3. The gecko interface of the servo type `Au`.

For code like `Size2D::new(Au(area.width), Au(area.height))` [1], should
we sprinkle nscoord's `value` member and use it like `area.width.value`?
Or can we convert `Au` to `nscoord` automatically? I haven't figured this out
yet.

[1] https://searchfox.org/mozilla-central/rev/2c1092dc68c63f7bad6da6a03c5883a5ab5ff2ca/servo/components/style/gecko/media_features.rs#26