bundlerepo: avoid exception in __del__ when the bundle doesn't exist
$ hg -R bundle://foo.hg
abort: No such file or directory: foo.hg
Exception exceptions.AttributeError: "'bundlerepository' object has no attribute 'bundlefile'" in <bound method bundlerepository.__del__ of <mercurial.bundlerepo.bundlerepository object at 0xa7ab9fac>> ignored
adding foo
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
foo
2ed2a3912a0b24502043eae84ee4b279c18b90dd 644 foo
pulling from http://localhost:20059/
searching for changes
no changes found