Android MoPub ProGuard警告，无法导出标志APK

使用MoPub集成时，无法导出带有ProGuard enable的签名APK，并出现以下警告：

Proguard returned with error code 1. See console
Warning: com.mopub.nativeads.MoPubRecyclerAdapter: can't find referenced method 'void notifyItemInserted(int)' in class com.mopub.nativeads.MoPubRecyclerAdapter
Warning: com.mopub.nativeads.MoPubRecyclerAdapter: can't find referenced method 'void notifyItemRemoved(int)' in class com.mopub.nativeads.MoPubRecyclerAdapter
Warning: com.mopub.nativeads.MoPubRecyclerAdapter$3: can't find referenced method 'void notifyDataSetChanged()' in class com.mopub.nativeads.MoPubRecyclerAdapter
Warning: com.mopub.nativeads.MoPubRecyclerAdapter$3: can't find referenced method 'void notifyItemRangeChanged(int,int)' in class com.mopub.nativeads.MoPubRecyclerAdapter
Warning: com.mopub.nativeads.MoPubRecyclerAdapter$3: can't find referenced method 'void notifyItemRangeInserted(int,int)' in class com.mopub.nativeads.MoPubRecyclerAdapter
Warning: com.mopub.nativeads.MoPubRecyclerAdapter$3: can't find referenced method 'void notifyItemRangeRemoved(int,int)' in class com.mopub.nativeads.MoPubRecyclerAdapter
You should check if you need to specify additional program jars.
Your input classes appear to be inconsistent.