AppDatabase.kt: Modify function with assigning method

Signed-off-by: 1552980358 <1552980358@qq.com>

app/src/main/java/io/legado/app/data/AppDatabase.kt

@@ -25,8 +25,8 @@ abstract class AppDatabase : RoomDatabase() {
         
         private const val DATABASE_NAME = "legado.db"
         
-        fun createDatabase(context: Context): AppDatabase {
-            return Room.databaseBuilder(context, AppDatabase::class.java, DATABASE_NAME)
+        fun createDatabase(context: Context) =
+            Room.databaseBuilder(context, AppDatabase::class.java, DATABASE_NAME)
                 .fallbackToDestructiveMigration()
                 .addMigrations(
                     migration_10_11,
@@ -41,7 +41,6 @@ abstract class AppDatabase : RoomDatabase() {
                 )
                 .allowMainThreadQueries()
                 .build()
-        }
         
         private val migration_10_11 = object: Migration(10, 11) {
             override fun migrate(database: SupportSQLiteDatabase) {