Inline readImageHeaderSubscription in PageHolder
Inline readImageHeaderSubscription in PagerPageHolder and
WebtoonPageHolder by converting setImage() into a suspend function.
The image processing runs in the loadPageAndProcessStatus
continuation.
Use suspendCancellableCoroutine as a substitute for doOnUnsubscribe
in WebtoonPageHolder.
Closing openStream after the frame.setImage but before the PageHolder
is recycled causes the page display to fail for reasons that are not
currently understood.
Remove subscription handling from WebtoonViewer/WebtoonBaseHolder as
it is no longer used.
(cherry picked from commit ffa8c8fd0746863e08b839f9d91102fe6d5d7887)
# Conflicts:
# app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/pager/PagerPageHolder.kt
# app/src/main/java/eu/kanade/tachiyomi/ui/reader/viewer/webtoon/WebtoonPageHolder.kt
725a66f078