Add constant folding for long unary operations in opt. compiler.

Add tests to exercise the constant folding of these
instructions.

Also, prevent Java methods from run-tests exercising the
code generation of these instruction from being inlined,
so that they continue to check the generated code (and
not the code produced by the constant folding pass).

Change-Id: I28efca7cdb5142ac2b6d158ba296fb9136d62481