Allow a message argument for __DEPRECATED_IN.

The messages come from a different CL in AOSP, but that CL breaks
internally because this code doesn't exist in AOSP. Merging the
compatibility thing first so I can land the rest in AOSP.

Bug: None
Test: None
Change-Id: I906c6ea7bd6d891aba9e185756131ac5b34f3c3d