Add AlignedAllocation.h.
Add AlignedAllocation.h.

I forgot to "git add" it in r308496.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@308498 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 8ccbaa6d612eac92d7ec4d0deff876d36d9510fd)

apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang