Fix crash because view.file_name() is None for console view
Fix crash because view.file_name() is None for console view

Fix #46

timonwong/OmniMarkupPreviewer,Lyleo/OmniMarkupPreviewer,timonwong/OmniMarkupPreviewer,Lyleo/OmniMarkupPreviewer,timonwong/OmniMarkupPreviewer,Lyleo/OmniMarkupPreviewer,timonwong/OmniMarkupPreviewer,Lyleo/OmniMarkupPreviewer