Move copyright and svn mime check presubmit checks to trigger on commit only.

Move copyright and svn mime check presubmit checks to trigger on commit only.

The commit bot automagically fixes these issues so the devs don't need to fix these problems

TEST=none
BUG=none
R=dpranke@chromium.org

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=84572

[Dirk Pranke, 2011-05-06 21:56:20]

LGTM.

I will note, though, that if the code that the commit bot was using to fix the
issues was being run though presubmit instead, you could fix these errors on
upload as well, which seems useful. It's not a big deal, though.