Convert GN visibility to lists.

Source/bindings/core/v8/BUILD.gn

 # Copyright 2014 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.
 
 import("//third_party/WebKit/Source/bindings/core/idl.gni")
 
 import("//third_party/WebKit/Source/bindings/core/v8/generated.gni")
 import("//third_party/WebKit/Source/bindings/scripts/scripts.gni")
 import("//third_party/WebKit/Source/core/core.gni")
 
-visibility = "//third_party/WebKit/Source/*"
+visibility = [ "//third_party/WebKit/Source/*" ]
 
 # bindings_core_v8_generated in core/v8/generated.gyp
 group("bindings_core_v8_generated") {
   deps = [
     ":bindings_core_dictionary_impl_generated",
     ":bindings_core_v8_generated_aggregate",
     ":bindings_core_v8_generated_individual",
   ]
 }
 
@@ skipping 12 matching lines @@
 
 # bindings_core_dictionary_impl_generated in Source/bindings/core/v8/generated.gyp
 idl_dictionary("bindings_core_dictionary_impl_generated") {
   # FIXME: Add 'core_dictionary_idl_files' to sources
   # See comment on core/core.gypi
   sources = core_testing_dictionary_idl_files
   # FIXME: Add 'generated_core_dictionary_files' to outputs
   # See comment on core/core.gypi
   outputs = generated_core_testing_dictionary_files
 }