Use mangleTemplatePrefix when we know that we're mangling a nested template name.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@82912 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGenCXX/mangle-subst.cpp b/test/CodeGenCXX/mangle-subst.cpp
index cda6df5..c53a630 100644
--- a/test/CodeGenCXX/mangle-subst.cpp
+++ b/test/CodeGenCXX/mangle-subst.cpp
@@ -46,3 +46,11 @@
 
 // CHECK: @_Z2f2IiEv1VIT_ENS2_1UE
 template void f2<int>(V<int>, int);
+
+namespace NS {
+template <typename T> struct S1 {};
+template<typename T> void ft3(S1<T>, S1<char>) {  }
+
+// CHECK: @_ZN2NS3ft3IiEEvNS_2S1IT_EENS1_IcEE
+template void ft3<int>(S1<int>, S1<char>);
+}