The getDecorView method return view include navigation bar view on lollipop？

I use SlidingMenu to implement my slide-in menus.

The code is

private void initSlidingMenu()
{
    // configure the SlidingMenu
    menu = new SlidingMenu(this);
    menu.setMode(SlidingMenu.LEFT);
    menu.setTouchModeAbove(SlidingMenu.TOUCHMODE_FULLSCREEN);
    menu.setShadowWidthRes(R.dimen.shadow_width);
    //        menu.setShadowDrawable(R.drawable.shadoew);
    menu.setBehindOffsetRes(R.dimen.slidingmenu_offset);
    //        menu.setFadeDegree(0.35f);
    menu.attachToActivity(this, SlidingMenu.SLIDING_WINDOW);
    menu.setMenu(R.layout.menu_main_sliding);
}

Then I got a problem is my layout behind of navigation bar.

And i change the SlidingMenu.SLIDING_WINDOW to SlidingMenu.SLIDING_CONTENT. It's works,but the actionbar always on the top.

Look at the source code of SlidingMenu,i find this code to add slidingmenu.

    switch (slideStyle) {
    case SLIDING_WINDOW:
        mActionbarOverlay = false;
        ViewGroup decor = (ViewGroup) activity.getWindow().getDecorView();
        ViewGroup decorChild = (ViewGroup) decor.getChildAt(0);
        // save ActionBar themes that have transparent assets
        decorChild.setBackgroundResource(background);
        decor.removeView(decorChild);
        decor.addView(this);
        setContent(decorChild);
        break;
    case SLIDING_CONTENT:
        mActionbarOverlay = actionbarOverlay;
        // take the above view out of
        ViewGroup contentParent = (ViewGroup)activity.findViewById(android.R.id.content);
        View content = contentParent.getChildAt(0);
        contentParent.removeView(content);
        contentParent.addView(this);
        setContent(content);
        // save people from having transparent backgrounds
        if (content.getBackground() == null)
            content.setBackgroundResource(background);
        break;
    }

How can i fix it? This bug only found in Android 5.0 lollipop.

SlidingMenu on GitHub has opened same issue.

private int getNavigationBarHeight() { 
    Resources resources = getResources();
    int resourceId = resources.getIdentifier("navigation_bar_height", "dimen", "android");
    if (resourceId > 0) {
        return resources.getDimensionPixelSize(resourceId);
    } 
    return 0; 
} 

@Override 
public void onCreate(Bundle savedInstanceState) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        int navBarHeight = getNavigationBarHeight();
        findViewById(R.id.base_frame).setPadding(0, 0, 0, navBarHeight);
        findViewById(R.id.menu_frame).setPadding(0, 0, 0, navBarHeight);
    } 
}