Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_4/rev/cad532eff7d7
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #18432 from zbraniecki/995425-upgrade-sinon

Bug 995425 - upgrade sinon to 1.9.1 and update API usage. r=julienw
(cherry picked from commit a338645d27c509f064ac3365ca2acc50a08fceb5)

Conflicts:
	apps/costcontrol/test/unit/widget_startup_test.js
Bumping manifests a=b2g-bump