Combine script profiling with profile crates. Fixes#7514.
The script crate had its own built-in profiling which was basically doing the same thing as the profile crate. This wraps the internal profiling around the main profile functionality. Script-related tasks are now added to the ProfilerCategory enum.
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Update prefs API to return an Option<bool>.
This allows for situations where there is no reasonable default
to apply for the pref value e.g. when we are just listing values
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Allow 'script' component to enter a 'built' state
After this pull request merged:
https://github.com/servo/servo/pull/7209
the 'script' component would never enter a 'built' state. In other
words, if one calls `mach build`, lets it complete, then calls `mach
build` again, the 'script' component would rebuild even though we
supposedly just built it. This was due to the `ParserResults.pkl`
getting placed in the `components/script` directory instead of the
output directory, causing cargo to think that there were unbuilt files.
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After this pull request merged:
https://github.com/servo/servo/pull/7209
the 'script' component would never enter a 'built' state. In other
words, if one calls `mach build`, lets it complete, then calls `mach
build` again, the 'script' component would rebuild even though we
supposedly just built it. This was due to the `ParserResults.pkl`
getting placed in the `components/script` directory instead of the
output directory, causing cargo to think that there were unbuilt files.
This replaces before_remove_attr(), after_remove_attr() and after_set_attr().
The virtual method takes the mutated attribute and an AttributeMutation value
to disambiguate between "attribute is changed", "attribute is added" and
"attribute is removed".
In the case of "attribute is changed", the mutation value contains a reference
to the old value of the mutated attribute, which is used to unregister outdated
named elements when the "id" attribute is changed on an element.
This greatly simplifies the handling of attributes, which in many cases don't
have any specific behaviour whether they are removed or changed or added. It
also fixes a few bugs where things were put in before_remove_attr() instead of
after_remove_attr() (e.g. when removing an href attribute from a base element).
A few helper functions in Element were also renamed and made private.
Cleanup/refactor build scripts for DOM codegen
Prior to this commit, the script codegen makefile relied on an
intermediary pythonpath.py file that handled python dependencies and
incorporated a couple hacks to get the codegen building working. This
commit removes that intermediary file and attempts to make the script
codegen build process cleaner.
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