/usr/share/lintian/overrides/icedtea-netx-common is in icedtea-netx-common 1.2.3-0ubuntu0.12.04.4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # handled by alternatives
icedtea-netx-common binary: desktop-command-not-in-package
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