Forward visibility explicitly in GN component.

build/config/BUILDCONFIG.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # =============================================================================
 # PLATFORM SELECTION
 # =============================================================================
 #
 # There are two main things to set: "os" and "cpu". The "toolchain" is the name
 # of the GN thing that encodes combinations of these things.
@@ skipping 582 matching lines @@
                           invoker.component_never_use_source_set
   assert(_never_use_source_set || true)  # Mark as used.
   if (is_component_build) {
     _component_mode = "shared_library"
   } else if (_never_use_source_set) {
     _component_mode = "static_library"
   } else {
     _component_mode = "source_set"
   }
   target(_component_mode, target_name) {
-    forward_variables_from(invoker, "*")
+    # Explicitly forward visibility, implicitly forward everything else.
+    # Forwarding "*" doesn't recurse into nested scopes (to avoid copying all
+    # globals into each template invocation), so won't pick up file-scoped
+    # variables. Normally this isn't too bad, but visibility is commonly
+    # defined at the file scope. Explicitly forwarding visibility and then
+    # excluding it from the "*" set works around this problem.
+    # See http://crbug.com/594610
+    forward_variables_from(invoker, [ "visibility" ])
+    forward_variables_from(invoker, "*", [ "visibility" ])
 
     # All shared libraries must have the sanitizer deps to properly link in
     # asan mode (this target will be empty in other cases).
     if (!defined(deps)) {
       deps = []
     }
     deps += [ "//build/config/sanitizers:deps" ]
   }
 }