Add 'static' and 'const' qualifiers to some arrays of strings.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@186314 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Format/BreakableToken.cpp b/lib/Format/BreakableToken.cpp
index 816fd23..3b29137 100644
--- a/lib/Format/BreakableToken.cpp
+++ b/lib/Format/BreakableToken.cpp
@@ -167,7 +167,7 @@
 }
 
 static StringRef getLineCommentPrefix(StringRef Comment) {
-  const char *KnownPrefixes[] = { "/// ", "///", "// ", "//" };
+  static const char *const KnownPrefixes[] = { "/// ", "///", "// ", "//" };
   for (size_t i = 0, e = llvm::array_lengthof(KnownPrefixes); i != e; ++i)
     if (Comment.startswith(KnownPrefixes[i]))
       return KnownPrefixes[i];