Merge "Address const issues in preparation for libcxx rebase." am: b2cb35e
am: 4e39764

* commit '4e3976417b4e43c2a3969fb3305d9f069ec8c8f8':
  Address const issues in preparation for libcxx rebase.

Change-Id: I7b25949ccdae45398f47c43f79fa532d66d4d3a2