Minor perf gain in value watch
Minor perf gain in value watch

Removes an ngClass and applies the needed class directly inside the
watch.

PonteIneptique/arethusa,alpheios-project/arethusa,alpheios-project/arethusa,PonteIneptique/arethusa,fbaumgardt/arethusa,Masoumeh/arethusa,Masoumeh/arethusa,fbaumgardt/arethusa,latin-language-toolkit/arethusa,alpheios-project/arethusa,fbaumgardt/arethusa,latin-language-toolkit/arethusa