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

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https://hg.mozilla.org/integration/gaia-1_4/rev/2f0f143bd33f
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #17987 from nullaus/v1.4

Merge pull request #17303 from nullaus/bug982006

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https://hg.mozilla.org/integration/gaia-1_4/rev/624f05fbeee8
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #17303 from nullaus/bug982006

bug 982006(cherry picked from commit 288c8763265aa98c16c8b79cddaf37c3dd34d2a2)

Conflicts:
	apps/system/test/unit/app_modal_dialog_test.js
Bumping manifests a=b2g-bump