Turn UdfpView into a SurfaceView

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

import android.graphics.PixelFormat;

import android.graphics.Rect;

import android.graphics.RectF;

import android.hardware.fingerprint.FingerprintSensorPropertiesInternal;

import android.util.AttributeSet;

import android.util.Log;

import android.view.Surface;

import android.view.View;

import android.view.SurfaceHolder;

import android.view.SurfaceView;

import android.view.ViewTreeObserver;

import com.android.systemui.R;

import com.android.systemui.doze.DozeReceiver;

import com.android.systemui.plugins.statusbar.StatusBarStateController;

import com.android.systemui.statusbar.StatusBarState;

import com.android.systemui.statusbar.phone.ScrimController;

/**

 * A full screen view with a configurable illumination dot and scrim.

 */

public class UdfpsView extends View implements DozeReceiver,

public class UdfpsView extends SurfaceView implements DozeReceiver,

        StatusBarStateController.StateListener,  ScrimController.ScrimChangedListener {

    private static final String TAG = "UdfpsView";

    // The runnable is reset to null after it's executed once.

    @Nullable private Runnable mRunAfterShowingScrimAndDot;

    @NonNull private final SurfaceHolder.Callback mSurfaceCallback = new SurfaceHolder.Callback() {

        @Override

        public void surfaceCreated(@NonNull SurfaceHolder holder) {

            Log.d(TAG, "Surface created");

            // SurfaceView sets this to true by default. We must set it to false to allow

            // onDraw to be called

            setWillNotDraw(false);

        }

        @Override

        public void surfaceChanged(@NonNull SurfaceHolder holder, int format,

                int width, int height) {

        }

        @Override

        public void surfaceDestroyed(@NonNull SurfaceHolder holder) {

            Log.d(TAG, "Surface destroyed");

            // Must not draw when the surface is destroyed

            setWillNotDraw(true);

        }

    };

    public UdfpsView(Context context, AttributeSet attrs) {

        super(context, attrs);

            a.recycle();

        }

        getHolder().addCallback(mSurfaceCallback);

        getHolder().setFormat(PixelFormat.TRANSLUCENT);

        mScrimRect = new Rect();

        mScrimPaint = new Paint(0 /* flags */);