Cleanup multiview support * Removed remaining mentions of ANGLE_multiview * Removed AST transformations used only in the side-by-side multiview implementation * Changed the type of the internal ViewID_OVR variable to use the dedicated qualifier * Removed side-by-side multiview support from the D3D11 renderer * Removed an unused helper for side-by-side multiview support from the OpenGL renderer * Removed obsoleted test suppressions Fixed: angleproject:3341 Change-Id: I5e0706cbf26ea820b51400124ddbf2624b738f17 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4660046 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com>