Description of problem:
dnf crashes on GPG key import with gpgme reporting "General error".

Version-Release number of selected component (if applicable):
1.1.9-2.fc24

How reproducible:
Unknown

Steps to Reproduce:
1. Remove one of the repository GPG signing keys from rpm keyring or use repository which key was'nt imported yet.
2. Try to install/update something from repository, which key was'nt imported
3. Agree with importing this key

Actual results:
dnf crashes with gpgme reporting "General error"

Expected results:
dnf imports GPG key and continue installing/updating packages.

Additional info:

Traceback: << EOF
Importing GPG key 0x81B46521:
 Userid     : "Fedora (24) <fedora-24-primary>"
 Fingerprint: 5048 BDBB A5E7 76E5 47B0 9CCC 73BD E983 81B4 6521
 From       : /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-24-x86_64
Is this ok [y/N]: y
Traceback (most recent call last):
  File "/usr/lib/python3.5/site-packages/dnf/repo.py", line 226, in perform
    return super(_Handle, self).perform(result)
  File "/usr/lib64/python3.5/site-packages/librepo/__init__.py", line 1506, in perform
    _librepo.Handle.perform(self, result)
librepo.LibrepoException: (25, 'repomd.xml GPG signature verification error: Bad GPG signature', 'Bad GPG signature')

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.5/site-packages/dnf/repo.py", line 592, in _handle_load
    return self._handle_load_with_pubring(handle)
  File "/usr/lib/python3.5/site-packages/dnf/repo.py", line 610, in _handle_load_with_pubring
    return self._handle_load_core(handle)
  File "/usr/lib/python3.5/site-packages/dnf/repo.py", line 603, in _handle_load_core
    result = handle.perform()
  File "/usr/lib/python3.5/site-packages/dnf/repo.py", line 230, in perform
    raise _DetailedLibrepoError(exc, source)
dnf.repo._DetailedLibrepoError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/bin/dnf", line 58, in <module>
    main.user_main(sys.argv[1:], exit_code=True)
  File "/usr/lib/python3.5/site-packages/dnf/cli/main.py", line 174, in user_main
    errcode = main(args)
  File "/usr/lib/python3.5/site-packages/dnf/cli/main.py", line 60, in main
    return _main(base, args)
  File "/usr/lib/python3.5/site-packages/dnf/cli/main.py", line 112, in _main
    cli.run()
  File "/usr/lib/python3.5/site-packages/dnf/cli/cli.py", line 1095, in run
    self._process_demands()
  File "/usr/lib/python3.5/site-packages/dnf/cli/cli.py", line 810, in _process_demands
    load_available_repos=lar)
  File "/usr/lib/python3.5/site-packages/dnf/base.py", line 239, in fill_sack
    self._add_repo_to_sack(r)
  File "/usr/lib/python3.5/site-packages/dnf/base.py", line 111, in _add_repo_to_sack
    repo.load()
  File "/usr/lib/python3.5/site-packages/dnf/repo.py", line 835, in load
    self._handle_load(handle)
  File "/usr/lib/python3.5/site-packages/dnf/repo.py", line 597, in _handle_load
    dnf.crypto.import_repo_keys(self)
  File "/usr/lib/python3.5/site-packages/dnf/crypto.py", line 62, in import_repo_keys
    make_ro_copy=False)
  File "/usr/lib/python3.5/site-packages/dnf/yum/misc.py", line 318, in import_key_to_pubring
    return True
  File "/usr/lib64/python3.5/contextlib.py", line 77, in __exit__
    self.gen.throw(type, value, traceback)
  File "/usr/lib/python3.5/site-packages/dnf/crypto.py", line 95, in pubring_dir
    yield
  File "/usr/lib/python3.5/site-packages/dnf/yum/misc.py", line 293, in import_key_to_pubring
    gpgme.editutil.edit_trust(ctx, k, gpgme.VALIDITY_ULTIMATE)
  File "/usr/lib64/python3.5/site-packages/gpgme/editutil.py", line 75, in wrapper
    ctx.edit(key, edit_callback, output)
gpgme.GpgmeError: (32, 1, 'General error')
EOF

Version of dnf and gpgme packages: << EOF
$ rpm -q dnf gpgme pygpgme gnupg2
dnf-1.1.9-2.fc24.noarch
gpgme-1.4.3-7.fc24.x86_64
pygpgme-0.3-15.fc24.x86_64
gnupg2-2.1.13-1.fc24.x86_64 
EOF