Description:
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mime_content_type() returns text/plain for gzip and bzip files.

I guess this function looks the type up in /etc/mime.types.

The extensions are not in there and should bot be in there.The comments in the file say:

Note: Compression schemes like "gzip", "bzip", and "compress" are notactually "mime-types".  They are "encodings" and hence must _not_ have entries in this file to map their extensions.  The "mime-type" of an encoded file refers to the type of data that has been encoded, not the type of encoding.

My Mail application relies on this function for attaching files from the filesystem. With this kind of files it failes.

Please fix this.


Reproduce code:
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run mime_content_type on a *.tar.gz file.

Expected result:
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return application/gzip or something like that

Actual result:
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returns text/plain