Revert "Revert "Fix builds with XCode 8 / OSX SDK 10.12""

This reverts commit 244916243b3eb807bad582f8285534469526af71.

We now use / require at least the 10.10 SDK to build this branch, so
this should be safe now.

Change-Id: I2e3a9b127d7e8f287f180015aa57389f26525fa9
1 file changed