Also remedies places where the video backends and core rely on things
being indirectly included.

Gets rid of magic numbers in cases where the array size is known at compile time.
This is also useful for future entries that are stack allocated arrays as these
functions prevent incorrect sizes being provided.

Only loop through and call getPointers when something has actually
changed.
Worth about 2-4% speedup un SMG over the previous commit.

Move ownership of cached_arraybases from CPMemory to VertexLoaderManager
to better match it usage.

This state will be used to calculate sizes for skipping over commands on
a separate thread.  An alternative to having these state variables would
be to have the preprocessor stash "state as we go" somewhere, but I
think that would be much uglier.

GetVertexSize now takes an extra argument to determine which state to
use, as does FifoCommandRunnable, which calls it.  While I'm modifying
FifoCommandRunnable, I also change it to take a buffer and size as
parameters rather than using g_pVideoData, which will also be necessary
later.  I also get rid of an unused overload.

The next commit will add a separate copy of the struct and the ability
for LoadCPReg to work on it.