[C++] Provide a variant of AppendValues that takes bytemaps for the nullability

[asfimport]

Instead of only accepting bitmaps, we should provide users with a variant of AppendValues that can work on bytemaps.

Reporter: Uwe Korn / @xhochy

_{Note: This issue was originally created as ARROW-2487. Please see the migration documentation for further details.}

[asfimport]

Kouhei Sutou / @kou:
There is already one use case.

C GLib bindings use gboolean for boolean value. bool in C99 is 1byte. So we can use bool value for the current valid_bytes. But gboolean isn't 1byte. It uses int (*1) as the real type.

(*1) https://developer.gnome.org/glib/stable/glib-Basic-Types.html#gboolean

If AppendValues accepts const int* for valid_bytes, we can remove type conversion (gboolean -> uint8_t) from C GLib bindings.

[asfimport]

Wes McKinney / @wesm:
Is this still an issue? We have AppendValues methods that accepts a byte vector argument for the validity markers

[asfimport]

Kouhei Sutou / @kou:
I think that we can close this.
We need AppendValues(const value_type* values, int64_t length, const int32_t* valid_bytes = NULLPTR) for my use case. But it's not suitable to handle in this issue. Because existing AppendValues() variants already accept bytemap. They just don't accept 4bytemap.