Fix Debian dependencies instructions
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Stylo: Update bindings for ServoType
This is needed for https://bugzilla.mozilla.org/show_bug.cgi?id=1348873
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Make ImageData::new return Fallible instead of unwrapping a result
Instead of unwrapping `new_with_jsobject` result, `ImageData::new` will just pass the error along.
It required tweaking `canvasrenderingcontext2d` as it no longer needs to assume the result is `Ok`.
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stylo: Sequentialize binding generation if logging is enabled.
Otherwise the log is useless, and it's even slower than in parallel mode due to
the high lock contention.
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Stylo: Add support for text-size-adjust property
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Gecko supports -{moz,webkit}-text-size-adjust properties, but it only supports auto and none value.
Implement parsing/serialization for text-size-adjust property and its gecko glue.
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Addresses #15401
The desired result is for `CSSWideKeyword`s to return false (they are
parsed) and other Custom declaration values to return true (they are unparsed).
This whole method was a large `if let` block:
```rust
if let Some(mut root_flow) = self.root_flow.clone() {
// ...
}
```
Move that `if let` to callers to make it clear that the method
doesn’t need to be called when `self.root_flow` is `None`.
By itself, this commit doesn’t change anything.
But it enables the next one.
Per-process lock for CSSOM objects
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Before this PR, every object reflected in CSSOM is in `Arc<RwLock<_>>` to enable safe (synchronized) mutable aliasing. Acquiring all these locks has significant cost during selector matching:
* https://bugzilla.mozilla.org/show_bug.cgi?id=1311469
* https://bugzilla.mozilla.org/show_bug.cgi?id=1335941
* https://bugzilla.mozilla.org/show_bug.cgi?id=1339703
This PR introduce a mechanism to protect many objects with the same `RwLock` that only needs to be acquired once.
In Stylo, there is one such lock per process (in a `lazy_static`), used for everything.
I non-Stylo Servo, I originally intended to have one such lock per document (for author-origin stylesheets, and one per process for user-agent and user sytlesheets since they’re shared across documents, and never mutated anyway). However I failed to have the same document-specific (or pipeline-specific) `Arc` reachable from both `Document` nodes and `LayoutThread`. Recursively following callers lead me to include this `Arc` in `UnprivilegedPipelineContent`, but that needs to be serializable. So there is a second process-wide lock.
This was previously #15998, closed accidentally.
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