Since ObjCARC has been refactored into its own library with its own declaration header, we need to include the declaration header alongside Scalar.h in BackendUtil.
Since ObjCARC has been refactored into its own library with its own declaration header, we need to include the declaration header alongside Scalar.h in BackendUtil.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@173648 91177308-0d34-0410-b5e6-96231b3b80d8

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