Convert GN visibility to be a list.

tools/gn/visibility_unittest.cc

 // 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.
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "tools/gn/err.h"
 #include "tools/gn/label.h"
 #include "tools/gn/value.h"
 #include "tools/gn/visibility.h"
 
@@ skipping 15 matching lines @@
   EXPECT_TRUE(vis.CanSeeMe(Label(SourceDir("//rec/a/"), "anything")));
   EXPECT_TRUE(vis.CanSeeMe(Label(SourceDir("//rec/b/"), "anything")));
   EXPECT_TRUE(vis.CanSeeMe(Label(SourceDir("//dir/"), "anything")));
   EXPECT_FALSE(vis.CanSeeMe(Label(SourceDir("//dir/a/"), "anything")));
   EXPECT_FALSE(vis.CanSeeMe(Label(SourceDir("//directory/"), "anything")));
 }
 
 TEST(Visibility, Public) {
   Err err;
   Visibility vis;
-  ASSERT_TRUE(vis.Set(SourceDir("//"), Value(NULL, "*"), &err));
+
+  Value list(NULL, Value::LIST);
+  list.list_value().push_back(Value(NULL, "*"));
+  ASSERT_TRUE(vis.Set(SourceDir("//"), list, &err));
 
   EXPECT_TRUE(vis.CanSeeMe(Label(SourceDir("//random/"), "thing")));
   EXPECT_TRUE(vis.CanSeeMe(Label(SourceDir("//"), "")));
 }
 
 TEST(Visibility, Private) {
   Err err;
   Visibility vis;
   ASSERT_TRUE(vis.Set(SourceDir("//"), Value(NULL, Value::LIST), &err));
 
   EXPECT_FALSE(vis.CanSeeMe(Label(SourceDir("//random/"), "thing")));
   EXPECT_FALSE(vis.CanSeeMe(Label(SourceDir("//"), "")));
 }