This is preparation for sharing this code with layout_2020 and
implementing selective off-the-main-thread animations.
We still look for nodes not in the flow tree in the layout thread.
There are a few canvas2d-related dependencies that haven't updated, but they
only use euclid internally so that's not blocking landing the rest of the
changes.
Given the size of this patch, I think it's useful to get this landed as-is.
Move display_list_builder.rs and webrender_helpers.rs
along with the new file to components/layout/display_list/
Remove apparently unused IdType enum.
Only variant used was OverflowClip.
See #19676
Servo currently uses `heapsize`, but Stylo/Gecko use `malloc_size_of`.
`malloc_size_of` is better -- it handles various cases that `heapsize` does not
-- so this patch changes Servo to use `malloc_size_of`.
This patch makes the following changes to the `malloc_size_of` crate.
- Adds `MallocSizeOf` trait implementations for numerous types, some built-in
(e.g. `VecDeque`), some external and Servo-only (e.g. `string_cache`).
- Makes `enclosing_size_of_op` optional, because vanilla jemalloc doesn't
support that operation.
- For `HashSet`/`HashMap`, falls back to a computed estimate when
`enclosing_size_of_op` isn't available.
- Adds an extern "C" `malloc_size_of` function that does the actual heap
measurement; this is based on the same functions from the `heapsize` crate.
This patch makes the following changes elsewhere.
- Converts all the uses of `heapsize` to instead use `malloc_size_of`.
- Disables the "heapsize"/"heap_size" feature for the external crates that
provide it.
- Removes the `HeapSizeOf` implementation from `hashglobe`.
- Adds `ignore` annotations to a few `Rc`/`Arc`, because `malloc_size_of`
doesn't derive those types, unlike `heapsize`.
Casting `*const T` to `*const U` with `U: Sized` is allowed even if `T: ?Sized`.
This safely extracts the data pointer out of a trait object,
without relying on the memory representation of trait objects.
The alias is left there temporarilly and will be removed completely in a later commit where
also components/style/gecko/generated/structs_{debug|release}.rs are re-generated (they still
use the old alias).
This allows us to have ensure_data() and clear_data() functions on the TElement
trait, instead of hacking around it adding methods in random traits.
This also allows us to do some further cleanup, which I'd rather do in a
followup.
This commit splits the style and layout data in two separate refcells.
These transmutes have been a source of trouble (for example on Android), and
they feel like a hack anyway.
Fixes#16982
Sometimes clippy gets outdated by months, and its current support setup
means that each Servo component need to opt into it by depending on
the plugins crate manually, and not all components do that.
Only create scroll roots for overflow regions when the overflow region
is actually larger than the container size. This prevents creating
scrolling roots for elements that do not have overflow scroll as a
side-effect of the way their height and width is defined. For example,
tables should never respect overflow:scroll since their height and
width should always be large enough to prevent overflow. This also
decreases the size and complexity of the display list in many other
circumstances.
As part of this change, transformed overflow calculation is moved from
display list construction to layout. This should mean that overflow is
handled more accurately earlier.
Fixes#14574.
