We don't use it, anyway.

Java inlines static finals if they're defined with a constant expression. In
case of version constants we don't want that to happen, since they obviously
change from version to version. If the user substitutes a different OpenCV
jar without recompiling, we want user code to still have relevant values for
the version constants.

This arranges that by turning constant values into function calls, which no
longer count as a constant expression.

Because apparently I love running performance tests for debug builds.

Signed-off-by: Han Qiang <a0byte@gmail.com>