Consider visibility attributes in namespaces as being explicit. I.e., they
take precedence over command line options. Fixes PR10113.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147405 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 842ce0f..b4a4eb1 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -300,7 +300,7 @@
         const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(DC);
         if (!ND) continue;
         if (llvm::Optional<Visibility> Vis = ND->getExplicitVisibility()) {
-          LV.setVisibility(*Vis, false);
+          LV.setVisibility(*Vis, true);
           F.ConsiderGlobalVisibility = false;
           break;
         }