Fix generation of v14 resources
generate_v14_compatible_resources.GenerateV14Resources was deleting and
recreating the output directory. process_resources was calling that
multiple times and reusing the same output directory (and so it would
only actually get v14 resources for the final directory).
Instead, callers of GenerateV14Resources should handle deleting/creating
the output directory for themselves--this is just
generate_v14_compatible_resources.main and process_resources (which was
already handling this itself).
BUG=383803
Review URL: https://codereview.chromium.org/
362543004
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@280725 0039d316-1c4b-4281-b951-d872f2087c98