/usr/lib/x86_64-linux-gnu/pkgconfig/mozjs-24.pc is in libmozjs-24-dev 24.2.0-3ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | prefix=/usr
libdir=/usr/lib/x86_64-linux-gnu/
includedir=/usr/include
Name: SpiderMonkey 24.2.0
Description: The Mozilla library for JavaScript
Version: 24.2.0
Requires.private: nspr >= 4.9.2
Libs: -L${libdir} -lmozjs-24
Cflags: -include ${includedir}/mozjs-24/js/RequiredDefines.h -I${includedir}/mozjs-24
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