[mob][photos] Add more fields in search filter models

mobile/lib/models/search/hierarchical/album_filter.dart

@@ -1,10 +1,18 @@
 import "package:flutter/material.dart";
 import "package:photos/models/search/hierarchical/hierarchical_search_filter.dart";
 
-class AlbumFilter implements HierarchicalSearchFilter {
+class AlbumFilter extends HierarchicalSearchFilter {
+  final int collectionID;
   final String albumName;
 
-  AlbumFilter(this.albumName);
+  ///Number of files in the gallery that are from [collectionID]
+  final int occurrence;
+
+  AlbumFilter({
+    required this.collectionID,
+    required this.albumName,
+    required this.occurrence,
+  });
 
   @override
   String name() {
@@ -15,4 +23,9 @@ class AlbumFilter implements HierarchicalSearchFilter {
   IconData icon() {
     return Icons.photo_library_outlined;
   }
+
+  @override
+  int relevance() {
+    return occurrence;
+  }
 }

mobile/lib/models/search/hierarchical/hierarchical_search_filter.dart

@@ -3,4 +3,5 @@ import "package:flutter/widgets.dart";
 abstract class HierarchicalSearchFilter {
   String name();
   IconData? icon();
+  int relevance();
 }