/usr/lib/x86_64-linux-gnu/pkgconfig/cairomm-pdf-1.0.pc is in libcairomm-1.0-dev 1.10.0-1ubuntu3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | Name: cairomm-pdf
Description: C++ wrapper for cairo - pdf support
Requires: cairomm-1.0 cairo-pdf
Version: 1.10.0
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