[Merge] lp:~brandontschaefer/libsdl/mir-include-sdl2-pc-fix into lp:ubuntu/libsdl2

[Brandon Schaefer]

Review: Disapprove

While this did fix the compiling issue, it didn't fix the issue where the mir header was being exposed. I've a new branch that fixes exposing the mir headers, which fixes this issue as well.

https://code.launchpad.net/~brandontschaefer/libsdl/forward-declare-1306629-fix/+merge/216641
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https://code.launchpad.net/~brandontschaefer/libsdl/mir-include-sdl2-pc-fix/+merge/216400
Your team Ubuntu branches is requested to review the proposed merge of lp:~brandontschaefer/libsdl/mir-include-sdl2-pc-fix into lp:ubuntu/libsdl2.