This mainly groups the state that is used for generating a new blit
routine into a second BlitState structure 'updateState'. It also
allowed for the FrameBuffer's own parameters to not have a 'dest'
prefix. Also, 'locked' was renamed to 'framebuffer', and 'target' to
'renderbuffer'.

Change-Id: I64e26f0b06f9f4419b8ca67e6fbb0dee8272898a
Reviewed-on: https://swiftshader-review.googlesource.com/11510Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>