Bug 876145: fix authentication dialog in browser (wrong attribute)

Replace l10n-id with data-l10n-id in browser. As it is, the
authentication dialog's title is always displayed in English.
Bug 879661 - Unit test of internet_sharing.js failed frequently.
Bug 879343 - [B2G][Buri][Unagi][Inbound Calls]User Cannot receive inbound calls
Merge pull request #10233 from hsinyi/bugzilla/879343

Bug 879343 - [B2G][Buri][Unagi][Inbound Calls]User Cannot receive inboun...
r=etienne
Merge pull request #10210 from huchengtw-moz/system/Bug_879661_unit_test_of_internet_sharing_failed

Bug 879661 - Unit test of internet_sharing.js failed frequently. r=@alivedise
Merge pull request #10126 from flodolo/fix-l10n

Bug 876145: l10n, fix localizability of title in authentication dialog (browser) r=benfrancis