Don't include _unittest.py files in `grit_info --inputs` output.

If only a test changes, it shouldn't affect the files created by grit, so
this is useless output.

Reduces the size of chrome's ninja files by about 120kB / 1%.

Review URL: https://codereview.chromium.org/125353002/


git-svn-id: http://grit-i18n.googlecode.com/svn/trunk@144 7262f16d-afe8-6277-6482-052fa10e57b1
Add a --depfile flag that explicitly names the generated depfile.

--depdir stays around, since the base directory of paths in the depfile needs
to be specified as well.

BUG=chromium:297672
Review URL: https://codereview.chromium.org/99463008/


git-svn-id: http://grit-i18n.googlecode.com/svn/trunk@145 7262f16d-afe8-6277-6482-052fa10e57b1