Input array length is implicitly set at link time, based on the geometry
shader's layout. Specifying the wrong value here is an error; specifying
no value is the same as getting it right. (inspired by a recent codegen
change)
Those files are still not in use (SCons will tyr to compile new CCGSubSurf files
but no code will be in use at all because those new files are fully wrapped by
ifdef WITH_OPENSUBDIV check).
Sergey Sharybin