This re-formats a few headers that had become out-of-sync with respect
to formatting since we ran clang-format on the whole codebase. There's
surprisingly few instances of it.
This change is almost fully mechanical. The only interesting change is in `generate_feature_test_macro_components.py` to generate `_LIBCPP_STD_VER >=` instead. To avoid churn in the git-blame this commit should be added to the `.git-blame-ignore-revs` once committed.
Reviewed By: ldionne, var-const, #libc
Spies: jloser, libcxx-commits, arichardson, arphaman, wenlei
Differential Revision: https://reviews.llvm.org/D143962
Instead of writing every character directly into the container by using
a `back_insert_iterator` the data is buffered in an `array`. This buffer
is then inserted to the container by calling its `insert` member function.
Since there's no guarantee every container's `insert` behaves properly
containers need to opt-in to this behaviour. The appropriate standard
containers opt-in to this behaviour.
This change improves the performance of the format functions that use a
`back_insert_iterator`.
Depends on D110495
Reviewed By: ldionne, vitaut, #libc
Differential Revision: https://reviews.llvm.org/D110497
