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

llvm-svn: 80383
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 15e8bc3..85b5963 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/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;