According to [1], Content-Transfer-Encoding can have one of the
following values (case insensitive): "BASE64" / "QUOTED-PRINTABLE" /
"8BIT" / "7BIT" / "BINARY" / x-token.
Values "8bit", "7bit", and "binary" all imply that NO encoding has been
performed.
"x-token" refers to a custom implementation that can be done, where the
encoding agent and the decoding agent must agree upon. This case is not
addressed by the patch.
"QUOTED-PRINTABLE" and "base64" encodings are addressed by this patch,
and the decoding is performed for all the multipart content types
currently supported.
[1]https://www.w3.org/Protocols/rfc1341/5_Content-Transfer-Encoding.html
Change-Id: Iac29f3a287bd478f7f0b55d9911ae47f3a5890fb
Closes-Bug: #1696420
2a5cd3a412