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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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
<!-- Either: -->
- [x] There are tests for these changes
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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”
The time taken by each chunk is uneven, with WPT-1 the longest
before this change at 30~45 minutes. This reduces it to 15~20 minutes.
Surprisingly, increasing the number of processes seems to also make
`test_element_in_collection` in `/webdriver/tests/execute_script/cyclic.py`
**unexpectedly pass**. This happened reliably in three different runs:
https://community-tc.services.mozilla.com/tasks/S9O27WJvSa6j2PSjcRcbBA/runs/2
hidden field named _charset_ now appears in FormData as UTF-8
<!-- Please describe your changes on the following line: -->
HTMLInputElement now has special case logic for putting a hidden field named `_charset_` in an entry set. To support this, the encoding used when constructing a form dataset is now being passed further down the callchain than it was before.
---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#25150
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- [X] There are tests for these changes
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Rename the ServoSrc type to ServoGstSrc to avoid a name clash
<!-- Please describe your changes on the following line: -->
There's a name clash with the type name `ServoSrc`.
---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#25051
- [x] These changes do not require tests because
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Add onformdata to GlobalEventHandlers
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1. Adding `onformdata` to GlobalEventHandlers interface and global_event_handlers macro.
2. Deleting related FAIL tests.
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#25183 (GitHub issue number if applicable)
<!-- Either: -->
- [x] There are tests for these changes OR
- [ ] These changes do not require tests because ___
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