Fix bug that caused us to have many duplicate registrations

Fix bug that caused us to have many duplicate registrations
recorded in extension prefs for override pages.

BUG=41442
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=44551

[Erik does not do reviews, 2010-04-14 17:19:32]

Do we need to go anything to clean up the existing bogus entries in people's
prefs?

http://codereview.chromium.org/1518028/diff/3001/4001
File chrome/browser/extensions/extension_dom_ui.cc (right):

http://codereview.chromium.org/1518028/diff/3001/4001#newcode234
chrome/browser/extensions/extension_dom_ui.cc:234: if (override_val ==
(*iter).second.spec())
ouch.  surprising that we didn't hit this before.

[Aaron Boodman, 2010-04-14 17:33:43]

On Wed, Apr 14, 2010 at 10:19 AM,  <[email protected]> wrote:
> Do we need to go anything to clean up the existing bogus entries in people's
> prefs?

Yeah I realized that in the shower this morning. Will send a new cl soon.

- a

[Aaron Boodman, 2010-04-14 20:40:11]

Ready for another look.

[Erik does not do reviews, 2010-04-14 20:48:42]

LGTM

http://codereview.chromium.org/1518028/diff/7001/5002
File chrome/browser/extensions/extension_dom_ui.cc (right):

http://codereview.chromium.org/1518028/diff/7001/5002#newcode48
chrome/browser/extensions/extension_dom_ui.cc:48: // De-dupes the items in
|list|. Assumes the values are strings.
Add comment referencing bug and mention that this could eventually be removed.

http://codereview.chromium.org/1518028/diff/7001/5002#newcode52
chrome/browser/extensions/extension_dom_ui.cc:52: // Loop backwards as we may be
removing items.
this also has the cool side effect of preserving precedence order.  very nice.