Сохранение состояния web-view

Возникла проблема с сохранением состояния WebView в приложении. Пишу приложение, задача открывать ресурс и страницы внутри него без перезагрузки. Пробовал кэшировать, сохранять куки. Но все тщетно. Насколько я понимаю, нужно копать в сторону:

WebView.saveState(Bundle state) и WebView.restoreState(Bundle state)

Так же мне не понятно, принципиально ли использовать сохранение кук, дом сторэдж и кэша в данном случаи.

MainActivity.java содержит следующий код:

public class MainActivity extends Activity {

    private static final String TAG = MainActivity.class.getSimpleName();
    @SuppressLint("SetJavaScriptEnabled")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        CookieManager.getInstance().setAcceptCookie(true);

        if (savedInstanceState == null) {
            Log.v(TAG, "MainFragment Creation");
            getFragmentManager().beginTransaction()
                    .add(R.id.container, new MainFragment())
                    .commit();
        }
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

MainFragment.java содержит:

public class MainFragment extends Fragment {

    private static final String TAG = MainFragment.class.getSimpleName();

    public static final int INPUT_FILE_REQUEST_CODE = 1;
    public static final String EXTRA_FROM_NOTIFICATION = "EXTRA_FROM_NOTIFICATION";

    private WebView mWebView;
    private ValueCallback<Uri[]> mFilePathCallback;
    private String mCameraPhotoPath;

    public MainFragment() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_main, container, false);

        // Get reference of WebView from layout/activity_main.xml
        mWebView = (WebView) rootView.findViewById(R.id.fragment_main_webview);

        setUpWebViewDefaults(mWebView);

        /*
        // Check whether we're recreating a previously destroyed instance
        if (savedInstanceState != null) {
            // Restore the previous URL and history stack
            mWebView.restoreState(savedInstanceState);
        }
        */

        mWebView.setWebChromeClient(new WebChromeClient() {
            public boolean onShowFileChooser(
                    WebView webView, ValueCallback<Uri[]> filePathCallback,
                    WebChromeClient.FileChooserParams fileChooserParams) {
                if(mFilePathCallback != null) {
                    mFilePathCallback.onReceiveValue(null);
                }
                mFilePathCallback = filePathCallback;

                Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                if (takePictureIntent.resolveActivity(getActivity().getPackageManager()) != null) {
                    // Create the File where the photo should go
                    File photoFile = null;
                    try {
                        photoFile = createImageFile();
                        takePictureIntent.putExtra("PhotoPath", mCameraPhotoPath);
                    } catch (IOException ex) {
                        // Error occurred while creating the File
                        Log.e(TAG, "Unable to create Image File", ex);
                    }

                    // Continue only if the File was successfully created
                    if (photoFile != null) {
                        mCameraPhotoPath = "file:" + photoFile.getAbsolutePath();
                        takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT,
                                Uri.fromFile(photoFile));
                    } else {
                        takePictureIntent = null;
                    }
                }

                Intent contentSelectionIntent = new Intent(Intent.ACTION_GET_CONTENT);
                contentSelectionIntent.addCategory(Intent.CATEGORY_OPENABLE);
                contentSelectionIntent.setType("image/*");

                Intent[] intentArray;
                if(takePictureIntent != null) {
                    intentArray = new Intent[]{takePictureIntent};
                } else {
                    intentArray = new Intent[0];
                }

                Intent chooserIntent = new Intent(Intent.ACTION_CHOOSER);
                chooserIntent.putExtra(Intent.EXTRA_INTENT, contentSelectionIntent);
                chooserIntent.putExtra(Intent.EXTRA_TITLE, "Image Chooser");
                chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, intentArray);

                startActivityForResult(chooserIntent, INPUT_FILE_REQUEST_CODE);

                return true;
            }
        });

        if (savedInstanceState == null) {
            mWebView.loadUrl("example.com");
        } else {
            mWebView.restoreState(savedInstanceState);
        }

        /*
        if (savedInstanceState != null)
            mWebView.restoreState(savedInstanceState);
        else
            mWebView.loadUrl("example.com");
        */
        /*
        // Load the local index.html file
        if(mWebView.getUrl() == null) {
            mWebView.loadUrl("example.com");
        }
        */
        /*
        if(webViewBundle == null)   { 
         mWebView.loadUrl("example.com");
        }   else   { 
         mWebView.restoreState ( webViewBundle ) ; 
        }
        */

        return rootView;
    }

    /**
     * More info this method can be found at
     * http://developer.android.com/training/camera/photobasics.html
     *
     * @return
     * @throws IOException
     */
    private File createImageFile() throws IOException {
        // Create an image file name
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        String imageFileName = "JPEG_" + timeStamp + "_";
        File storageDir = Environment.getExternalStoragePublicDirectory(
                Environment.DIRECTORY_PICTURES);
        File imageFile = File.createTempFile(
                imageFileName,  /* prefix */
                ".jpg",         /* suffix */
                storageDir      /* directory */
        );
        return imageFile;
    }

    /**
     * Convenience method to set some generic defaults for a
     * given WebView
     *
     * @param webView
     */
    @SuppressLint("SetJavaScriptEnabled")
    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    private void setUpWebViewDefaults(WebView webView) {
        WebSettings settings = webView.getSettings();

        webView.getSettings().setAppCacheEnabled(false);
        webView.getSettings().setCacheMode(WebSettings.LOAD_NO_CACHE);

        webView.getSettings().setJavaScriptEnabled(true);
        webView.setWebChromeClient(new WebChromeClient());
        webView.getSettings().setDomStorageEnabled(true);
        webView.getSettings().setAllowFileAccess(true);

        // Enable Javascript
        settings.setJavaScriptEnabled(true);
        webView.getSettings().setDomStorageEnabled(true);

        // Use WideViewport and Zoom out if there is no viewport defined
        settings.setUseWideViewPort(true);
        settings.setLoadWithOverviewMode(true);

        // Enable pinch to zoom without the zoom buttons
        settings.setBuiltInZoomControls(true);

        if(Build.VERSION.SDK_INT > Build.VERSION_CODES.HONEYCOMB) {
            // Hide the zoom controls for HONEYCOMB+
            settings.setDisplayZoomControls(false);
        }

        // Enable remote debugging via chrome://inspect
        if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            WebView.setWebContentsDebuggingEnabled(true);
        }

        // We set the WebViewClient to ensure links are consumed by the WebView rather
        // than passed to a browser if it can
        mWebView.setWebViewClient(new WebViewClient());
    }

    @Override
    public void onActivityResult (int requestCode, int resultCode, Intent data) {
        if(requestCode != INPUT_FILE_REQUEST_CODE || mFilePathCallback == null) {
            super.onActivityResult(requestCode, resultCode, data);
            return;
        }

        Uri[] results = null;

        // Check that the response is a good one
        if(resultCode == Activity.RESULT_OK) {
            if(data == null) {
                // If there is not data, then we may have taken a photo
                if(mCameraPhotoPath != null) {
                    results = new Uri[]{Uri.parse(mCameraPhotoPath)};
                }
            } else {
                String dataString = data.getDataString();
                if (dataString != null) {
                    results = new Uri[]{Uri.parse(dataString)};
                }
            }
        }

        mFilePathCallback.onReceiveValue(results);
        mFilePathCallback = null;
        return;
    }
}