Format unions like structs and classes.

Note that I don't know whether we should put {} on a single line in this
case, but it is probably a theoretical issue as in practice such
structs, classes or unions won't be empty.

Before: union A {}
        a;
After:  union A {} a;

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172355 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Format/UnwrappedLineParser.cpp b/lib/Format/UnwrappedLineParser.cpp
index 0c8ff89..b3671b3 100644
--- a/lib/Format/UnwrappedLineParser.cpp
+++ b/lib/Format/UnwrappedLineParser.cpp
@@ -317,7 +317,8 @@
     case tok::kw_enum:
       parseEnum();
       return;
-    case tok::kw_struct:  // fallthrough
+    case tok::kw_struct: // fallthrough
+    case tok::kw_union:  // fallthrough
     case tok::kw_class:
       parseStructClassOrBracedList();
       return;