Fixes gh-8041
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| Q | A <!--(Can use an emoji 👍) -->
| ------------------------ | ---
| Fixed Issues? | #8041
| Patch: Bug Fix? |👍
| Major: Breaking Change? |
| Minor: New Feature? |
| Tests Added + Pass? | Yes
| Documentation PR | <!-- If so, add `[skip ci]` to your commit message to skip CI -->
| Any Dependency Changes? |
| License | MIT
<!-- Describe your changes below in as much detail as possible -->
* Update decorators parsing
This commit introduces three changes:
1) Class properties can be decorated
2) Decorators can contain arbitrary expressions, using @(...)
3) The Decorator node type has a new property, "arguments". This
makes it possible do distinguish @dec() and @(dec()), which have
different behaviors because @(dec()) is equivalent to @(dec())().
* Rename Decorator#expression to Decorator#callee
* Add test for @dec()()
