Rather than expose the bounding box members directly, we can instead
provide an interface for code to use. This makes it nicer to transition
from global data, as the interface function names are already in
place.
This header doesn't actually make use of MathUtil.h within itself, so
this can be removed. Many other source files used VideoCommon.h as an
indirect include to include MathUtil.h, so these includes can also be
adjusted.
While we're at it, we can also migrate valid inclusions of VideoCommon.h
into cpp files where it can feasibly be done to minimize propagating it
via other headers.
Greatly simplifies the overall interface when it comes to compiling
shaders. Also allows getting rid of a std::string overload of the same
name. Now std::string and const char* both go through the same function.
Also makes y_scale a dynamic parameter for EFB copies, as it doesn't
make sense to keep it as part of the uid, otherwise we're generating
redundant shaders.
Also skips swapping the window system buffers in headless mode, as there
may not be a surface which can be swapped in the first place. Instead,
we call glFlush() at the end of a frame in this case.
