Import MutableArrayRef into clang namespace.

llvm-svn: 211988
diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index 92a3033..1cb6ab5 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -3422,8 +3422,8 @@
 
     // <seq-id> is encoded in base-36, using digits and upper case letters.
     char Buffer[7]; // log(2**32) / log(36) ~= 7
-    llvm::MutableArrayRef<char> BufferRef(Buffer);
-    llvm::MutableArrayRef<char>::reverse_iterator I = BufferRef.rbegin();
+    MutableArrayRef<char> BufferRef(Buffer);
+    MutableArrayRef<char>::reverse_iterator I = BufferRef.rbegin();
 
     for (; SeqID != 0; SeqID /= 36) {
       unsigned C = SeqID % 36;