Bug 1018214 - adding a number of gaia ui tests for status bar and utility tray accessibility. r=Bebe
Bug 1021710 - updating accessibility.js to use standard marionette timeout instead of it's arbitrary one when retrieving an accessible object.
Merge pull request #20508 from yzen/bug-1018214

Bug 1018214, Bug 1021710 - utility tray gaia-ui tests with some tweaks to hopefully avoid intermittents.