Took out the special mouseover cancel case
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eventtarget.rs was checking the event type to see if it was a mouseover; now it doesn't. Other special-case events like error and beforeunload go down other code paths entirely, so this one has no special cases left.
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Remove unnecessary thread in filereader, add stream TODO
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I think there are no benefits to queuing the various `FileReadingTask` from a thread, and reading the actual blob bytes are still done on the main-thread. We could try to move the reading off the main-thread(but note the `Blob` is not something you would want to move to another thread "as-is" since it's a `DomObject`), and I think we should just aim for implementing streams and follow the spec instead.
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Workarounds for form-submission-0 tests with about:blank onloads
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Following the model of 3b9ab34600 these changes replace some naive onload events with equivalents that do nothing if they see an about:blank load event. Two test cases now pass, and one failing test case is now failing for a less ambiguous reason (#25154)
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Enable some mach commands to be run with python3
This change finally enable the following commands to be run with python3:
* `build`
* `test-unit`
* `package`
As previously explained, `test-tidy` will require more work in the wpt repository directly. Maybe `test-tidy --no-wpt` is achievable relatively quickly though.
For possible remaining bits that might need to be worked on, see https://github.com/servo/servo/issues/23607
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Percentage `width` are treated as `auto` for the purpose of
min/max-content computation, so they also need to be considered
when testing “wether width is auto”
