Two fixes to how we compute visibility:

* Handle some situations where we should never make a decl more visible,
  even when merging in an explicit visibility.

* Handle attributes in members of classes that are explicitly specialized.

Thanks Nico for the report and testing, Eric for the initial review, and dgregor
for the awesome test27 :-)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151236 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaTemplate.cpp b/lib/Sema/SemaTemplate.cpp
index 2c98d0a..986a4c8 100644
--- a/lib/Sema/SemaTemplate.cpp
+++ b/lib/Sema/SemaTemplate.cpp
@@ -5350,6 +5350,7 @@
 /// \brief Strips various properties off an implicit instantiation
 /// that has just been explicitly specialized.
 static void StripImplicitInstantiation(NamedDecl *D) {
+  // FIXME: "make check" is clean if the call to dropAttrs() is commented out.
   D->dropAttrs();
 
   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {