Fix regression: Make view mode selectors for database collections show again

src/libtomahawk/database/DatabaseCollection.cpp

@@ -39,6 +39,10 @@ using namespace Tomahawk;
 DatabaseCollection::DatabaseCollection( const source_ptr& src, QObject* parent )
     : Collection( src, QString( "dbcollection:%1" ).arg( src->nodeId() ), parent )
 {
+    m_browseCapabilities
+        << CapabilityBrowseArtists
+        << CapabilityBrowseAlbums
+        << CapabilityBrowseTracks;
 }