If a preferences file references a theme which is from an old version, or who...

If a preferences file references a theme which is from an old version, or whose images have failed to process correctly, drop back to the default theme.

BUG= http://crbug.com/20263
TEST= Use a preferences file from an older version of Chrome that has a theme installed, and open Chrome.  Observe that Chrome opens using the default theme.


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=24830

[Miranda Callahan, 2009-08-28 21:45:15]

This forces anybody with an old non-cached-style theme to get on the
cached-theme train.

I wish I could command this code to self-destruct after it has run once, because
it really shouldn't be taking up time and space for a check that should only
happen a single time, and only for those relatively few people who have already
installed themes.

[tony, 2009-08-28 21:50:56]

LGTM.  If you wanted, you could add a UMA metric for how often this code runs. 
Once we stop seeing it in the logs, you can remove the migration code.

[Miranda Callahan, 2009-08-28 22:05:15]

Oh, very interesting, that's a great idea -- thanks, I'll do that!