Implement Legacy and base configuration

Implement legacy and base configuration as first configuration from linkerconfig.
Implement backward compatibility test to track folders from vendor.

Bug: 123722631
Test: m -j && atest
Change-Id: I2a33faffa03a73bd2ed0bfe92de367d635767472
diff --git a/modules/environment.cc b/modules/environment.cc
new file mode 100644
index 0000000..71ade6b
--- /dev/null
+++ b/modules/environment.cc
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linkerconfig/environment.h"
+
+#include "linkerconfig/variables.h"
+
+namespace android {
+namespace linkerconfig {
+namespace modules {
+bool IsLegacyDevice() {
+  // TODO : Implement
+  auto legacy_device = Variables::GetValue("is_legacy").value_or("false");
+
+  return legacy_device == "true";
+}
+
+bool IsVndkInSystemNamespace() {
+  // TODO : Implement
+  return true;
+}
+
+std::string GetVendorVndkVersion() {
+  return Variables::GetValue("ro.vndk.version").value_or("");
+}
+}  // namespace modules
+}  // namespace linkerconfig
+}  // namespace android
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