Add FlagManager SF class.
To handle Mendel experiment flags and system properties. Example method
is `demo_flag`.
Bug: 190769260
Test: make, atest libsurfaceflinger_unittest
Change-Id: If42630dc9c545d4117b616e862a21970193eda56
diff --git a/services/surfaceflinger/FlagManager.h b/services/surfaceflinger/FlagManager.h
new file mode 100644
index 0000000..65e30a4
--- /dev/null
+++ b/services/surfaceflinger/FlagManager.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2021 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.
+ */
+
+#pragma once
+
+#include <cstdint>
+#include <optional>
+#include <string>
+
+namespace android {
+// Manages flags for SurfaceFlinger, including default values, system properties, and Mendel
+// experiment configuration values.
+class FlagManager {
+public:
+ FlagManager() = default;
+ virtual ~FlagManager();
+ void dump(std::string& result) const;
+
+ int64_t demo_flag() const;
+
+private:
+ friend class FlagManagerTest;
+
+ // Wrapper for mocking in test.
+ virtual std::string getServerConfigurableFlag(const std::string& experimentFlagName) const;
+
+ template <typename T>
+ T getValue(const std::string& experimentFlagName, std::optional<T> systemPropertyOpt,
+ T defaultValue) const;
+};
+} // namespace android