Steps to reproduce:

1. Make sure solr service is running;
2. Login to admin interface;
3. Create the following content structure:

Home
	Tests				(folder, location_id: 122)
	TestMoveParent			(folder, location_id: 123)
		TestMoveChild		(article, location_id: 124)

4. Go into the Sorl admin interface and search for "TestMove*". You will find "TestMoveParent" and "TestMoveChild". Please note the main_location_path_id:

name_s: "TestMoveParent",
main_location_path_id: "/1/2/123/",
...
name_s: "TestMoveChild",
main_location_path_id: "/1/2/123/124/",

5. Go back to the eZ Publish admin interface and move the "TestMoveParent" into another location. In this test, it was moved under "Home/Tests". The content structure is now this:

Home
	Tests					(folder, location_id: 122)
		TestMoveParent			(folder, location_id: 123)
			TestMoveChild		(article, location_id: 124)

6. Go back to the Sorl admin interface and search for "TestMove*" again. You will see that the main_location_path_id has been changed for the "TestMoveParent", but not for the "TestMoveChild":

"name_s": "TestMoveParent",
"main_location_path_id": "/1/2/122/123/",			=> correct
...
"name_s": "TestMoveChild",
"main_location_path_id": "/1/2/123/124/",			=> wrong, should be "/1/2/122/123/124"