AI 143632: am: CL 143504 Completed cstddef to be non empty and similar to the gnu...

AI 143632: am: CL 143504 Completed cstddef to be non empty and similar to the gnu stl implementation.
  Even if we don't want to have a bloated stl implementation, having empty
  files around is probably not very good either.
  Added a test to make sure the header file compiles on host and kila-eng.
  QA Impact: In system/extras/test/bionic/libstdc++ build the tests using:
  mm BIONIC_TESTS=1
  to build the host and target tests.
  Original author: niko
  Merged from: //branches/donutburger/...

Automated import of CL 143632