[modules] Remove dead code from Module for tracking macro import locations.

llvm-svn: 236376
diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 1251e98..21dccd1 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -752,7 +752,7 @@
     if (getLangOpts().Modules) {
       Imported = TheModuleLoader.loadModule(ModuleImportLoc,
                                             ModuleImportPath,
-                                            Module::MacrosVisible,
+                                            Module::Hidden,
                                             /*IsIncludeDirective=*/false);
       if (Imported)
         makeModuleVisible(Imported, ModuleImportLoc);