* tests/js/parsing/class_mixin.js: support
* tests/js/parsing/class_extends_dot.js: support
[hackjs] support 'class' as a property name

Test Plan:
./pfff -parse_js ~/www
=> 93.54%

Reviewers: avik, jeffmo

Reviewed By: avik

Differential Revision: https://phabricator.fb.com/D998806
[hackjs] support JSX in more context

Test Plan:
./pfff -parse_js ~/www
94.18%

Reviewers: avik, jeffmo

Reviewed By: avik

Differential Revision: https://phabricator.fb.com/D998812
* lang_php/analyze/visual/highlight_php.ml: fix highlight of fields
* lang_php/analyze/visual/highlight_php.ml: clean
* code_map/model2.ml: try colorize methods and PHP fields