Initial stub migrate to androidx room

app/src/main/java/com/hippo/ehviewer/dao/EhDatabase.java

@@ -0,0 +1,23 @@
+package com.hippo.ehviewer.dao;
+
+import androidx.room.Database;
+import androidx.room.RoomDatabase;
+
+@Database(entities = {BookmarkInfo.class, DownloadInfo.class, DownloadLabel.class, DownloadDirname.class, Filter.class, HistoryInfo.class, LocalFavoriteInfo.class, QuickSearch.class}, version = 4, exportSchema = false)
+public abstract class EhDatabase extends RoomDatabase {
+    public abstract BookmarksBao bookmarksBao();
+
+    public abstract DownloadDirnameDao downloadDirnameDao();
+
+    public abstract DownloadLabelDao downloadLabelDao();
+
+    public abstract DownloadsDao downloadsDao();
+
+    public abstract FilterDao filterDao();
+
+    public abstract HistoryDao historyDao();
+
+    public abstract LocalFavoritesDao localFavoritesDao();
+
+    public abstract QuickSearchDao quickSearchDao();
+}