SSAA relies on MSAA being active to work. We only supports 4x SSAA while in fact you can enable SSAA at any MSAA level.
I even managed to run 64xMSAA + SSAA on my Quadro which made some pretty sleek looking games. They were very cinematic though.
With this, it properly fixes up SSAA and MSAA support in GLES as well. Before they were broken when stereo rendering was enabled.
Now in GLES they can properly support MSAA and also stereo rendering with MSAA enabled(with proper extensions).
This is good hygiene, and also happens to be required to build Dolphin
using Clang modules.
(Under this setup, each header file becomes a module, and each #include
is automatically translated to a module import. Recursive includes
still leak through (by default), but modules are compiled independently,
and can't depend on defines or types having previously been set up. The
main reason to retrofit it onto Dolphin is compilation performance - no
more textual includes whatsoever, rather than putting a few blessed
common headers into a PCH. Unfortunately, I found multiple Clang bugs
while trying to build Dolphin this way, so it's not ready yet, but I can
start with this prerequisite.)