Don't reset the shortcuts immediately but when the shortcuts dialog is
closed
Issue 6941 (Ctrl+Shift+C launches Firefox devtools' inspector instead of
Firebug's one)
http://code.google.com/p/fbug/issues/detail?id=6941
Put disabling existing shortcuts into its own function (related to issue
6991)
Put Firebug shortcuts into their own keyset
Disable existing browser shortcuts after Firebug extension activation
Revert shortcuts to defaults when Firebug extension is disabled
Issue 6991 (Ctrl+Shift+C conflicts with Firefox DevTools' Inspector)
http://code.google.com/p/fbug/issues/detail?id=6991

React to the "devtools-loaded" event to override global shortcuts
Store the disabled shortcuts in the chrome window instead of
BrowserCommands to allow resetting the shorcuts to the defaults
Merge branch 'issue6991b'