Add link to the MDN page to the wiki link as it has better instructions.
Bug 859354 - Add and alerting tone when a second call is waiting.
r=gtorodelvalle
Merge pull request #9151 from etiennesegonzac/bug-859354-call-waiting-alert

Bug 859354 - Add and alerting tone when a second call is waiting.
Merge pull request #8856 from jwoodcock/master

Bug 855369 Added link to MDN to supplement the wiki link r=julien
Bug 862716 - Avoiding lazy load of contacts order