[PATCH] MS ABI: Avoid hashing back reference keys in mangler

[Timur Iskhodzhanov]

Funny.

Agreed to David's comment, otherwise LGTM.

================
Comment at: lib/AST/MicrosoftMangle.cpp:999
@@ -1009,1 +998,3 @@
   if (Found == NameBackReferences.end()) {
+    if (NameBackReferences.size() < 10) {
+      NameBackReferences.push_back(Name);
----------------
nit: `{}` not needed anymore?

http://reviews.llvm.org/D5430