/etc/apache2/conf.d/charset is in apache2.2-common 2.2.22-1ubuntu1.
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 | # Read the documentation before enabling AddDefaultCharset.
# In general, it is only a good idea if you know that all your files
# have this encoding. It will override any encoding given in the files
# in meta http-equiv or xml encoding tags.
#AddDefaultCharset UTF-8
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