Bug 1817796 - Adjust smiley and embarassed smiley-to-emoji conversion....

Bug 1817796 - Adjust smiley and embarassed smiley-to-emoji conversion. r=necko-reviewers,valentin, a=dmeehan

Adjust the smiley icon.
Also adjust embarassed detection which was wrong. The :-[ is more like bummed I think, but it's also "bat" so given it's not always clear what it means, probably best to not convert that.
Embarrassed emoji according to https://en.wikipedia.org/wiki/List_of_emoticons

Differential Revision: https://phabricator.services.mozilla.com/D179904