Can anyone upstream my changes

[mccakit]

I'm sorry but creating a PR for skia looks very weird, so I'm just submitting my changes to the mirror in hope it someone can actuaally upstream my changes.

This PR adds mingw support to skia, it does this by checking the target triplet, and using either is_msvc or is_mingw, to fix header conflicts with rfc.h, some files have interface keyword replaced with iface

[skia-codereview-bot]

This PR (HEAD: a82704e) has been imported to Gerrit for code review.

Please visit review.skia.org/1107780 to see it. Please CC yourself to the Gerrit change.

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[HinTak]

You can file your changes at https://issues.skia.org (you just need a Gmail account) for consideration and discussion. You get much better responses than doing pulls here. I believe doing pulls here you end up having to pass review at https://reviews.skia.prg anyway, so you might as well post your suggestions at *.skia.org .