Bumping gaia.json for 2 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_4/rev/cca76e7f9742
Author: sprd-ffos <ying.xu@spreadtrum.com>
Desc: Merge pull request #20124 from timdream/keyboard-dbltap-back-v1.3t

Bug 1020628 - (1.3t) Don't allow user to start activity twice in keyboard settings +shepherd
Conflicts:
	apps/keyboard/js/settings/settings.js

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https://hg.mozilla.org/integration/gaia-1_4/rev/21edc5f8de0d
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #18736 from alivedise/bugzilla/1002316_v1.3t_real/sound-manager-home-event

Bug 1002316 - Homescreen event should be caught by sound manager, r=timdream
Bumping manifests a=b2g-bump