[modules] When we try to complete the redeclaration chain for a class template
specialization, pull in any lazy specializations of the class template.

llvm-svn: 227668
diff --git a/clang/test/Modules/merge-template-members.cpp b/clang/test/Modules/merge-template-members.cpp
new file mode 100644
index 0000000..99696d8
--- /dev/null
+++ b/clang/test/Modules/merge-template-members.cpp
@@ -0,0 +1,10 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -I%S/Inputs/merge-template-members -verify %s
+// expected-no-diagnostics
+
+template<typename> struct A { int n; };
+template<typename> struct B { typedef A<void> C; };
+template class B<int>;
+
+#include "update.h"
+B<int>::C use2;