Store latest redeclaration for each redeclarable template declaration

This patch adds a Latest field to RedeclarableTemplateDecl's CommonBase
class which is used to store the latest redeclaration.

llvm-svn: 109755
diff --git a/clang/lib/Frontend/PCHWriterDecl.cpp b/clang/lib/Frontend/PCHWriterDecl.cpp
index 3ac4958..75045eb 100644
--- a/clang/lib/Frontend/PCHWriterDecl.cpp
+++ b/clang/lib/Frontend/PCHWriterDecl.cpp
@@ -852,6 +852,8 @@
     Writer.AddDeclRef(D->getInstantiatedFromMemberTemplate(), Record);
     if (D->getInstantiatedFromMemberTemplate())
       Record.push_back(D->isMemberSpecialization());
+
+    Writer.AddDeclRef(D->getCommonPtr()->Latest, Record);
   }
 }