Add test for exact search with album query

tests/local/test_search.py

@@ -0,0 +1,16 @@
+from __future__ import unicode_literals
+
+import unittest
+
+from mopidy.local import search
+from mopidy.models import Album, Track
+
+
+class LocalLibrarySearchTest(unittest.TestCase):
+    def test_find_exact_with_album_query(self):
+        expected_tracks = [Track(album=Album(name='foo'))]
+        tracks = [Track(), Track(album=Album(name='bar'))] + expected_tracks
+
+        search_result = search.find_exact(tracks, {'album': ['foo']})
+
+        self.assertEqual(search_result.tracks, tuple(expected_tracks))