The core fonts themselves are maintained by Ascender. I don't know if
anyone from Ascender follows this list (or if anyone here has contacts
I can imagine 3 approaches:
-Coordinate with Ascender to have them include the glyphs into their
copy of the fonts. In that case it might be easier if the new glyphs
were licensed as Apache2 instead of being public domain, though
Ascender would know best what works for them.
-Submit them as separate font files, and have a build-time tool that
combines them with Ascender's fonts to create single ttf files that
Android can use.
-Submit them as separate font files and install them as such on
Android, and modify Android's run-time code to fall back to reading
those glyphs from the separate files.
Jean-Baptiste M. "JBQ" Queru
Software Engineer, Android Open-Source Project, Google.
Questions sent directly to me that have no reason for being private
will likely get ignored or forwarded to a public forum with no further