This commit reviews all continue uses in core happening within a
loop / switch / case hierarchy. This does not cover:
- Changes to libraries. Will be handled in another issue / commit.
- Uses out from loops, will be reviewed by other commit.
The policy followed has been:
- When possible, take rid of the continue.
- When clearly the intention was to jump to next element in loop
change to continue 2
- When it was not clear, keep old behavior switching to break, no
matter how weird the behavior may be.
Without this, its possible to get a document in the editpdf conversion queue
that keeps failing - and in some cases completely crashing the PHP script
despite exception handling - which ends up blocking the processing of the queue
entirely.
This change allows for a configurable number of attempts the conversion
task will perform before removing the item from the queue.
If the user is removed from a course after a submission has been made,
the task will crash and never continue. This removes submissions from
the cron task if the user isn't enrolled in the course.
