Disable Purplebox on Firefox Android

[benstrumeyer]

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Remove purple box on android FF

[christophertino]

This will work for new installs, but existing users would not be affected since the Conf property has already been set. We need to add a check in the init flow to turn off this setting for FFA users.

Check background.js initializeGhosteryModules. Above function scheduledTasks() , throw in a quick check for FFA and then add conf.show_alert = false.