tests/test-diff-issue2761.t

narrow: remove custom filelog type

This functionality is now handled by core as of the previous commit.

I wanted this to be a standalone commit because the deleted code
makes a reference to remotefilelog's file type missing a node() method
and this may have implications to narrow+remotefilelog usage. The code
in core doesn't perform this check and therefore behavior may be subtly
different and buggy.

But I /think/ the check is merely a performance optimization and
nothing more. So I'm optimistic this will continue to "just work."

Differential Revision: https://phab.mercurial-scm.org/D4644

Test issue2761

  $ hg init

  $ touch to-be-deleted
  $ hg add
  adding to-be-deleted
  $ hg ci -m first
  $ echo a > to-be-deleted
  $ hg ci -m second
  $ rm to-be-deleted
  $ hg diff -r 0

Same issue, different code path

  $ hg up -C
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ touch does-not-exist-in-1
  $ hg add
  adding does-not-exist-in-1
  $ hg ci -m third
  $ rm does-not-exist-in-1
  $ hg diff -r 1