Fix ASTMatchersNodeTest to work on Windows.
Fix ASTMatchersNodeTest to work on Windows.

It was failing because it had an explicit check for whether we're on
Windows.

There are a few other similar explicit checks in this file which I
didn't remove because they serve as reasonable documentation that the
test doesn't work with a Windows triple.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@274269 91177308-0d34-0410-b5e6-96231b3b80d8

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