Style refactoring: Refactor reformatter_test to properly set styles.
Style refactoring: Refactor reformatter_test to properly set styles.

Now each TestCase in reformatter_test explicitly sets the style it works with in
setUpClass. _ParseAndUnwrap doesn't need a special indent argument any longer.
By default, most reformatter_test currently tests Google style. Add explicit
tests for the differences in PEP8 style.

dmoliveira/yapf,lucius-feng/yapf,thurday/yapf,ambv/yapf,nikolamilosevic86/yapf,elviswf/yapf,google/yapf,bygloam/yapf,google/yapf,sbc100/yapf,jamesblunt/yapf,wklken/yapf,hayd/yapf,abduld/yapf,sbc100/yapf