Bug 1071505 - use constant GUIDs for Places roots. r=mano
Bug 1071505 - use constant GUIDs for Places roots (test changes). rs=mano

--HG--
rename : toolkit/components/places/tests/migration/places_v6_no_frecency.sqlite => toolkit/components/places/tests/migration/places_v6.sqlite
rename : toolkit/components/places/tests/migration/test_current_from_v10.js => toolkit/components/places/tests/migration/test_current_from_v16.js
rename : toolkit/components/places/tests/migration/test_database_from_v6_no_frecency.js => toolkit/components/places/tests/migration/test_current_from_v6.js