Make base::Value::TYPE a scoped enum.

components/prefs/pref_registry.cc

Index: components/prefs/pref_registry.cc
diff --git a/components/prefs/pref_registry.cc b/components/prefs/pref_registry.cc
index c42e77f74aa09fa36bba0a9db0d3785b7f1acfa3..63b5e6a823eb0ace7a7280aae3efb36bc3ece547 100644
--- a/components/prefs/pref_registry.cc
+++ b/components/prefs/pref_registry.cc
@@ -54,8 +54,8 @@ void PrefRegistry::RegisterPreference(const std::string& path,
                                       base::Value* default_value,
                                       uint32_t flags) {
   base::Value::Type orig_type = default_value->GetType();
-  DCHECK(orig_type != base::Value::TYPE_NULL &&
-         orig_type != base::Value::TYPE_BINARY) <<
+  DCHECK(orig_type != base::Value::Type::NONE &&
+         orig_type != base::Value::Type::BINARY) <<
          "invalid preference type: " << orig_type;
   DCHECK(!defaults_->GetValue(path, NULL)) <<
       "Trying to register a previously registered pref: " << path;