Convert old-style exception handling to current format in fix_encoding.py.
Convert old-style exception handling to current format in fix_encoding.py.

With this change, fix_encoding can be imported in python3.
fix_encoding.fix_encoding() returns False because, at least on my Ubuntu 14.04
system running python 3.4.3;

  sys.getdefaultencoding() == 'utf-8'

The Windows specific code hasn't been tested on python3 and is expected to
require fixes.

R=vapier@chromium.org
BUG=61357

Review URL: https://codereview.chromium.org/1710553003

git-svn-id: fd409f4bdeea2bb50a5d34bb4d4bfc2046a5a3dd@298834 0039d316-1c4b-4281-b951-d872f2087c98

primiano/depot_tools,primiano/depot_tools,primiano/depot_tools,CoherentLabs/depot_tools,CoherentLabs/depot_tools