Standardize x-mac-greek, x-mac-centraleurroman, and x-mac-turkish

[annevk]

WebKit still supports these encodings and is reluctant to remove them as it would more likely negatively impact end users than improve matters. As they are all straightforward single-byte encodings would there be interest from others on adding these to the web platform?

They are conveniently documented on Wikipedia:

• https://en.wikipedia.org/wiki/MacGreek_encoding
• https://en.wikipedia.org/wiki/Mac_OS_Central_European_encoding
• https://en.wikipedia.org/wiki/Mac_OS_Turkish_encoding

cc @hsivonen @inexorabletash

[inexorabletash]

Can you point to web content that's failing due to lack of support?

@ricea may have opinions here.

[ricea]

I'm opposed to supporting more legacy encodings. It undermines our push to get everyone on UTF-8.

In this case, the encodings have been obsolete for 20 years, and I can't find any demand from users to support them.

I honestly doubt anyone would notice if WebKit removed support.