Use default initializers (NFC)
Use default initializers (NFC)

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@308756 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 57df523425bb05a046d158dba2590bfe90f8b5ce)

apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm