Assert mini editor focus in a way that’s compatible with the shadow DOM
Assert mini editor focus in a way that’s compatible with the shadow DOM

This change makes the specs compatible with both pre- and
post-shadow-DOM text editors.
gvanderest/fuzzy-finder,viddo/fuzzy-finder,gvanderest/fuzzy-finder,Kerruba/fuzzy-finder,atom/fuzzy-finder,viddo/fuzzy-finder,nielsAD/fuzzy-finder,Kerruba/fuzzy-finder,toshi-saito/fuzzy-finder,segiddins/fuzzy-finder,Spy-Seth/fuzzy-finder,nielsAD/fuzzy-finder,pombredanne/fuzzy-finder,pombredanne/fuzzy-finder,segiddins/fuzzy-finder,Spy-Seth/fuzzy-finder