Merge "Address const issues in preparation for libcxx rebase." am: a4f7dad am: 3cc69fa
am: 8afff3b

* commit '8afff3bfe18320cece8b5601478a34c313a5ad46':
  Address const issues in preparation for libcxx rebase.

Change-Id: Ic64c71deda5f1ca154f2e3fd281500e7142eff6b