[gjs] (12 commits) ...Merge branch 'trampoline-cleanups' into 'master'

[Philip Chimento <pchimento src gnome org>]

Summary of changes:

  84cc8d8... function: Make gjs_callback_trampoline_ref to return the st
  e2f9cf8... function: Use gatomicrefcount for trampoline refcounting
  f298f86... function: Define a trampoline autopointer cleanup function 
  621e952... function: Cleanup the completed trampolines removal in one 
  8d38437... function: Use more auto pointers for base info
  e81a7b5... engine: Cleanup leftover async calls trampolines on gc
  79be1af... arg-cache: Make it clearer how we handle the trampoline ref
  8b42e17... function: Use a vector to hold the completed trampolines
  7f8cd63... jsapi-util: Mark some GjsAutoPointer operations as constexp
  cecbb49... function: Use c++ features to handle GjsCallbackTrampoline
  f970b78... function: Split trampoline callback handler removing goto
  7eefd99... Merge branch 'trampoline-cleanups' into 'master'