commands: fix typo in debugobsolete docstring

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branch : stable
extra : amend_source : 3e65891ccb84c77cc75f0b64b5f0ea2c6773b30a
hgweb: show correct error message for i18n environment

If exception is error.LookupError and running in i18n environment,
below condition is always true.
Because msg is translated and dosen't contain 'manifest'.

    if util.safehasattr(err, 'name') and 'manifest' not in msg:

This patch creates a new exception class and uses it instead of
string match.

--HG--
branch : stable
extra : rebase_source : 1d8338be268f32c013799ca24208ec6eca7f174b
Added tag 2.5.3 for changeset 50c922c1b514

--HG--
branch : stable
Added signature for changeset 50c922c1b514

--HG--
branch : stable