RK 7.1，增加默认锁屏壁纸：

frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java

private static final boolean ENABLE_LOCKSCREEN_WALLPAPER = true;

要设置出厂默认锁屏壁纸，修改如下代码即可实现：

frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/LockscreenWallpaper.java

public Bitmap getBitmap() {

if (mCached) {

return mCache;

}

if (!mWallpaperManager.isWallpaperSupported()) {

mCached = true;

mCache = null;

return null;

}

LoaderResult result = loadBitmap(mCurrentUserId, mSelectedUser);

if (result.success) {

mCached = true;

mUpdateMonitor.setHasLockscreenWallpaper(result.bitmap != null);

mCache = result.bitmap;

}

//add begin : 第一次开机加载失败，尝试读取系统资源default_