Fix typo that resulted in names at TU scope getting lost sometimes after a
module import.

llvm-svn: 202771
diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
index 6c9d5ca..2ca4911 100644
--- a/clang/lib/AST/DeclBase.cpp
+++ b/clang/lib/AST/DeclBase.cpp
@@ -1293,7 +1293,7 @@
       return R.first->second.getLookupResult();
 
     ExternalASTSource *Source = getParentASTContext().getExternalSource();
-    if (Source->FindExternalVisibleDeclsByName(this, Name) || R.second) {
+    if (Source->FindExternalVisibleDeclsByName(this, Name) || !R.second) {
       if (StoredDeclsMap *Map = LookupPtr.getPointer()) {
         StoredDeclsMap::iterator I = Map->find(Name);
         if (I != Map->end())