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

extensions/utility/unpacker.cc

Index: extensions/utility/unpacker.cc
diff --git a/extensions/utility/unpacker.cc b/extensions/utility/unpacker.cc
index 3620f38800b93d96d1041966442f25fc0cb3f681..cec0db865396eb10f0b4a6d5dc1f3143caf53a05 100644
--- a/extensions/utility/unpacker.cc
+++ b/extensions/utility/unpacker.cc
@@ -164,7 +164,7 @@ std::unique_ptr<base::DictionaryValue> Unpacker::ReadManifest(
     return nullptr;
   }
 
-  if (!root->IsType(base::Value::TYPE_DICTIONARY)) {
+  if (!root->IsType(base::Value::Type::DICTIONARY)) {
     *error = errors::kInvalidManifest;
     return nullptr;
   }