code: function(owner) {
  			this._commitUndo();
  			var change = new CompoundChange(owner);
  			this.add(change);
  			this.compoundChange = change;
  			this.compoundChange.start(this.view);
  			return this.compoundChange;
  		}
docs: Starts a compound change.
  <p>
  All changes added to stack from the time startCompoundChange() is called
  to the time that endCompoundChange() is called are compound on one change that can be un-done or re-done
  with one single call to undo() or redo().
  </p>
  
  @param owner the owner of the compound change which is called for start, end, undo and redo.
  
  @return the compound change
  
  @see orion.editor.UndoStack#endCompoundChange