style: Cleanup traversal.rs
Mostly reflowing comments that have become too long or two short with
refactorings, and using consistent indentation.
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remove various things now that Rust 1.17 is required
std::ptr::eq and Arc::ptr_eq are now usuable, and we can replace a
panic!() with abort().
- [X] `./mach build -d` does not report any errors
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- [X] These changes do not require tests because they are trivial replacements.
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When stylo is not enabled in Gecko, the global state initialization
still creates the style thread pool, even when it's not going to be
used. This wastes address space and a little memory.
See https://bugzilla.mozilla.org/show_bug.cgi?id=1374824#c38 and
following comment.
Add get_zero_value for IntermediateSVGPaint.
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This is a PR for https://bugzilla.mozilla.org/show_bug.cgi?id=1371199
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There are tests for these changes, a test case will be landed in reftests in https://bugzilla.mozilla.org/show_bug.cgi?id=1371199
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Bump cssparser version to 0.16.1 in toml files
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`ElementStyles` holds an optional list of values for each eager pseudo-element.
However, the type was declared as a slice instead of a fixed size array, so an
extra 8 bytes were being allocated to hold the size, even though it never
changes.
Moving the constant size into the type reduces `ElementStyles` and `ElementData`
by 8 bytes.
MozReview-Commit-ID: GaO6DKFxUMo
Before this change, the `ComputedStyle` struct that is part of permanent style
data per element holds 2 `StrongRuleNode`s (unvisited and visited) and 2
`Arc<ComputedValues>` (unvisited and visited).
Both rule nodes and the visited values don't actually need to be here. This
patch moves these 3 to new temporary storage in `CascadeInputs` on
`CurrentElementInfo` during the match and cascade process. Rule nodes are
pushed down inside the `ComputedValues` for later access after the cascade.
(Visited values were already available there.)
The permanent style data per element now has just the `Arc<ComputedValues>` for
itself and eager pseudo-elements (plus the `RestyleHint`).
MozReview-Commit-ID: 3wq52ERMpdi
In the patch after this, the existing `ComputedStyle` type is renamed and
repurposed as temporary storage of inputs for the cascade. To make it a bit
easier to follow what code is new, this patch starts by copying `ComputedStyle`
to context.rs without changes.
MozReview-Commit-ID: 41COA5rEoz7
Implement webkit prefixed values for display property
Added -webkit-{flex,inline-flex} values as flex, inline-flex. I didn't do this gecko only since that doesn't require anything in layout side.
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- [X] These changes fix#15400 (github issue number if applicable).
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style: Be more strict when setting the root font size.
Before this commit, we assumed that if the element had no parent element, it was
the root of the document, which is plain false, since we can arrive there from,
let's say, getComputedStyle on a detached node.
Bug: 1374062
Reviewed-By: heycam
MozReview-Commit-ID: 65DxdzXgd0J
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This is important because we're about to start storing a parallel list
of pushed hashes, and the current behavior here will cause mismatches
there.
We take the opportunity to bump the SmallVec size to 16, since each
entry is only a word and we really want to avoid heap-allocating. And
then we switch to drain(), because of
https://github.com/rust-lang/rust/issues/42763
Right now when calling getComputedStyle with an element from another document,
we return the style using the pres context of that document, not of the document
of the window getComputedStyle was called on, so this holds.
But it will stop holding if we ever change this, so assert it doesn't happen.
Bug: 1374062
Reviewed-By: Manishearth
MozReview-Commit-ID: 3g8yQWWdsen
