Validate FS (and RS) ASTs.
This change adds a new RSCheckAST class that is used to handle validation
of the final AST. The checks include existing RS checks (for accepted types)
and new checks for Filterscript (like disallowing pointers, unions and
> 32 bit types completely). The refactoring also fixes a subtle union bug
that existed in prior versions of llvm-rs-cc. We also add an implicit
pragma for "rs_fp_relaxed" by default on Filterscript.
Bug: 7166741
Change-Id: Ia077783b4caba0bbd89df2ab3827e9f4d1009eea
24 files changed