So that we can effectively decide if we need to perform additional
system calls to figure out what really happened.

It's more pythonic, and the `_event_type` implementation wasn't quite
usable anyway.

NB: the representation is not truly copy/paste python code if there is
a double quote inside event.path, but that should be a rare case so we
don't add the expensive special case handling there.

Some Python debuggers create additional threads, so we shouldn't assume that there is only one.

It might be even better to check for the emitter class, as opposed to platform

Reduce the amount of 'silent breakage'

So that we can avoid a race between test setup and fseventsd

While the `filesystem_view` helps with filtering out additional
`FileCreatedEvent`+`DirModifiedEvent` pairs then it also introduces
a huge amount of edge cases for synthetic events caused by move and
rename operations. On top of that, in order to properly resolve
those edge cases we'd have to go back to a solution very similar to
the old directory snapshots, with all the performance penalties they
suffered from...

As such I think it's better to acknowledge the behaviour for coalesced
events instead, and thus remove the `filesystem_view` again.