Auto merge of #16322 - tamamu:place-shorthand, r=upsuper

Implement alignment shorthand properties

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I implemented the shorthand properties, but it may includes some bugs.

Currently, `mach test-unit -p style` caught some errors (see #15954). I already tried `mach build-geckolib`, though there is no improvement. Please check my code.

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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 #15954

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- [x] There are tests for these changes

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