Make compare function in r342648 have strict weak ordering.
Make compare function in r342648 have strict weak ordering.

Comparison functions used in sorting algorithms need to have strict weak
ordering.  Remove the assert and allow comparisons on all lists.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@342774 91177308-0d34-0410-b5e6-96231b3b80d8

apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang