Bug 940669 - add button menu to toggle toolbars in Australis' customize mode, r=mconley

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extra : rebase_source : 096d92876f4827251fd534f7ea76b8dbfd81a691
Bug 958300 - [Australis] UITour: Add ability to query whether Sync is enabled. r=mhammond,Unfocused
Bug 956946 - Align menu top to URL bar. r=bnicholson
Bug 952092 - Get rid of post data in SessionStore r=smacleod
first work on broadcasting shistory