repo: Remove JSClass macros

The macros in jsapi-class.h are not needed here. Instead of using
JS_InitClass() which requires a constructor and prototype object, we can
just use JS_NewObject() which will use a plain object as the prototype,
and we don't need to store private data in the instances since there is
none.
16 jobs for remove-jsclass-macros-from-repo in 2 minutes and 43 seconds (queued for 1 second)
Status Job ID Name Coverage
  Source Check
passed #1000020
build_recommended

00:01:09

passed #1000021
cppcheck

00:00:18

passed #1000022
cpplint

00:01:11

passed #1000023
eslint

00:01:11

passed #1000024
iwyu

00:00:26

 
  Test
passed #1000026
build_maximal

00:01:31

passed #1000027
build_minimal

00:00:42

passed #1000025
asan
sanitizer_gcc

00:01:09

 
  Manual
manual #1000028
allowed to fail manual
coverage
manual #1000031
allowed to fail manual
installed_tests
manual #1000029
allowed to fail manual
iwyu-full
manual #1000030
asan allowed to fail manual
sanitizer_clang
manual #1000032
allowed to fail manual
valgrind
manual #1000035
allowed to fail manual
zeal_11
manual #1000033
allowed to fail manual
zeal_2
manual #1000034
allowed to fail manual
zeal_4