We were using `Object.create` to setup the prototype chain at the start of the class definition, which lead to #7771.
I was a bit worried about a speed hit, but it seems everyone optimizes the two patterns the same way.
https://jsbench.github.io/#f9fca52407643d96458a35763b201215Fixes#7771.
* #7349
- Add "use strict" directive to transformed class bodies
* Update tests (#7349)
* Add test for program with use strict directive (#7349)
* Update tests (#7349)
* Update source mapping (#7349)
* Add test for parent blockStatement with use strict directive (#7349)
* Update tests (#7349)
* Update tests (#7349)
* Update tests (#7349)
* Add test for constructor-only class (#7349)
* Constructor only classes are strict, too
But constructor only that use non-simple parameters must use a strict function wrapper.
* Fix test
* Wrapper not needed if class is already strict
* Revert change to lerna.json
* Update line endings in test fixtures to match current output
* Fix incorrectly set up static-property-tdz fixtures
It seems the fixture runner does not look into subfolders.
* Remove expected file that should not exist
* Reenable disable optimisation test
* Reenable disabled nbsp tests
* Reenable comments between props test
The comments adjacent to children test is still broken so it stays off.
* Add JSX Fragments to babel-types
* Support JSX fragments in the transform-react-jsx plugin
* Add tests JSX fragments
* Update helper-builder and transform plugin documentations for jsx fragment
* Add generator for jsx fragments
* Add test for jsx fragment generator
* Split jsx transform example into normal and fragment examples
* Remove unnecessary fields from ElementState in babel-helper-builder-react-jsx
* inline [skip ci]
* Added tests for ifThrowNamespace flag
* JSX transformator could work with XMLNamespaces (ifThrowNamespace flag)
* Use template literal instead
* Attempt to reword the message
* Added docs
* Reworded docs
* Reworded docs
* Fixed missing space in error message
* centralize plugin options
* Centralize plugins options
- move more options to the top
- move validations that depend on options to the top
* use isLoose option
* Move more validations to the top
* Move ref parameter for rewriteModuleStatementsAndPrepareHeader() to the top
* fix eslint errors
* remove unused parameter
* set default systemGlobal value
* Revert "Move ref parameter for rewriteModuleStatementsAndPrepareHeader() to the top"
This reverts commit b3855302d17fa19d8acb4c8accab3680c8d2710e.
* Revert "Move more validations to the top"
This reverts commit e5861d8a034ff8f553391f55654f753bcf428a5d.
* fix allowMutablePropsOnTags option usage
* improve naming
* change Contructor definition for sake of consistency
* move allowMutablePropsOnTags validation to the top
* add missing !
