WindowServer: Move the CPU monitor thingy to its own class.

Servers/WindowServer/WSCPUMonitor.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <AK/CircularQueue.h>
+
+class Painter;
+class Rect;
+
+class WSCPUMonitor {
+public:
+    WSCPUMonitor();
+
+    bool is_dirty() const { return m_dirty; }
+    void set_dirty(bool dirty) { m_dirty = dirty; }
+    int capacity() const { return m_cpu_history.capacity(); }
+    void paint(Painter&, const Rect&);
+
+private:
+    void get_cpu_usage(unsigned& busy, unsigned& idle);
+
+    CircularQueue<float, 30> m_cpu_history;
+    bool m_dirty { false };
+};