Merge pull request ipfs/go-unixfs#72 from ipfs/fix/remove-urlstore-sp…

…ecial-case

chore: remove URL field

This commit was moved from ipfs/go-unixfs@7cfc32e

unixfs/ipld-merkledag/importer/helpers/dagbuilder.go

@@ -65,11 +65,6 @@ type DagBuilderParams struct {
 	// NoCopy signals to the chunker that it should track fileinfo for
 	// filestore adds
 	NoCopy bool
-
-	// URL if non-empty (and NoCopy is also true) indicates that the
-	// file will not be stored in the datastore but instead retrieved
-	// from this location via the urlstore.
-	URL string
 }
 
 // New generates a new DagBuilderHelper from the given params and a given
@@ -87,10 +82,6 @@ func (dbp *DagBuilderParams) New(spl chunker.Splitter) (*DagBuilderHelper, error
 		db.stat = fi.Stat()
 	}
 
-	if dbp.URL != "" && dbp.NoCopy {
-		db.fullPath = dbp.URL
-	}
-
 	if dbp.NoCopy && db.fullPath == "" { // Enforce NoCopy
 		return nil, ErrMissingFsRef
 	}