Always allocate room for a ModuleDecl on the TranslationUnitDecl.
Always allocate room for a ModuleDecl on the TranslationUnitDecl.

Sometimes we create the ASTContext and thus the TranslationUnitDecl before we know the LangOptions. This should fix the asan buildbot failures after r312467.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@312506 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,llvm-mirror/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,llvm-mirror/clang,llvm-mirror/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