Android GL Context Loss

package com.diamondtools.opengl;

import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;

import android.app.Activity;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager.NameNotFoundException;
import android.opengl.GLSurfaceView;

import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;

public class MainActivity extends Activity {

    static {
        System.loadLibrary("DiamondTools");
    }

    private native int Activity_Pause();

    private native int Activity_DrawFrame();

    private native int Activity_SurfaceChange(int width, int height);

    private native int Activity_SurfaceCreate(String filePath);

    class EngineRenderer implements GLSurfaceView.Renderer {

        public void Destroy() {
            Activity_Pause(); // Destroys and cleans up textures + native objects
        }

        @Override
        public void onDrawFrame(GL10 gl) {
            Activity_DrawFrame(); // Calls GLES draw routines
        }

        @Override
        public void onSurfaceChanged(GL10 gl, int width, int height) {
            Activity_SurfaceChange(width, height); // Set viewport, rebuilds camera matrix
        }

        @Override
        public void onSurfaceCreated(GL10 gl, EGLConfig config) {
            ApplicationInfo ai = null;
            try {
                ai = getPackageManager()
                        .getApplicationInfo(getPackageName(), 0);
            } catch (NameNotFoundException e) {
                e.printStackTrace();
            }

            if (ai != null) {
                Activity_SurfaceCreate(ai.sourceDir); // Create native objects with path to APK for resources
            }
        }
    }

    private GLSurfaceView glSurfaceView = null;
    private EngineRenderer renderer = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        glSurfaceView = new GLSurfaceView(this);
        renderer = new EngineRenderer();

        glSurfaceView.setEGLContextClientVersion(2);
        glSurfaceView.setRenderer(renderer);

        glSurfaceView.setPreserveEGLContextOnPause(true); // Does nothing at all...

        setContentView(glSurfaceView);
    }

    @Override
    public void onPause() {
        super.onPause();

        if (renderer != null) {
            glSurfaceView.onPause();
            renderer.Destroy(); // Deconstruct the native objects + gl textures
        }
    }

    @Override
    public void onResume() {
        super.onResume();

        if (renderer != null) {
            glSurfaceView.onResume();
        }
    }
}