Refactor implementation constants.

Bug 19353282

Change-Id: If2eb9f2d78c3a44b720bb1f223711411b576d710
Reviewed-on: https://swiftshader-review.googlesource.com/5140
Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>
35 files changed