Check for UnresolvedUsingDecl when determining if a declaration is a redeclaration or not.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@80383 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 15e8bc3..85b5963 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -2899,7 +2899,7 @@
     if (PrevDecl && 
         (!AllowOverloadingOfFunction(PrevDecl, Context) || 
          !IsOverload(NewFD, PrevDecl, MatchedDecl)) &&
-        !isa<UsingDecl>(PrevDecl)) {
+        !isa<UsingDecl>(PrevDecl) && !isa<UnresolvedUsingDecl>(PrevDecl)) {
       Redeclaration = true;
       Decl *OldDecl = PrevDecl;