Android: Implement TLB optimization to prevent deadlocks and improve performance

src/input_common/drivers/touch_screen.h

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+// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <optional>
+
+#include "input_common/input_engine.h"
+
+namespace InputCommon {
+
+/**
+ * A touch device factory representing a touch screen. It receives touch events and forward them
+ * to all touch devices it created.
+ */
+class TouchScreen final : public InputEngine {
+public:
+    explicit TouchScreen(std::string input_engine_);
+
+    /**
+     * Signals that touch has moved and marks this touch point as active
+     * @param x new horizontal position
+     * @param y new vertical position
+     * @param finger_id of the touch point to be updated
+     */
+    void TouchMoved(float x, float y, std::size_t finger_id);
+
+    /**
+     * Signals and creates a new touch point with this finger id
+     * @param x starting horizontal position
+     * @param y starting vertical position
+     * @param finger_id to be assigned to the new touch point
+     */
+    void TouchPressed(float x, float y, std::size_t finger_id);
+
+    /**
+     * Signals and resets the touch point related to the this finger id
+     * @param finger_id to be released
+     */
+    void TouchReleased(std::size_t finger_id);
+
+    /// Resets the active flag for each touch point
+    void ClearActiveFlag();
+
+    /// Releases all touch that haven't been marked as active
+    void ReleaseInactiveTouch();
+
+    /// Resets all inputs to their initial value
+    void ReleaseAllTouch();
+
+private:
+    static constexpr std::size_t MAX_FINGER_COUNT = 16;
+
+    struct TouchStatus {
+        std::size_t finger_id{};
+        bool is_enabled{};
+        bool is_active{};
+    };
+
+    std::optional<std::size_t> GetIndexFromFingerId(std::size_t finger_id) const;
+
+    std::optional<std::size_t> GetNextFreeIndex() const;
+
+    std::array<TouchStatus, MAX_FINGER_COUNT> fingers{};
+};
+
+} // namespace InputCommon