Add missing `self = [super init]` statements. Those were reported by the static analyzer.
Pull request: https://github.com/WebKit/WebKit/pull/17894
Committed 268125@main (45dd419f3fea): <https://commits.webkit.org/268125@main> Reviewed commits have been landed. Closing PR #17894 and removing active labels.
<rdar://problem/115727213>