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

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https://hg.mozilla.org/integration/gaia-1_4/rev/52f6a8f2a024
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #18761 from nullaus/v1.4

Merge pull request #18698 from nullaus/bug999511

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https://hg.mozilla.org/integration/gaia-1_4/rev/3c405283ec24
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #18698 from nullaus/bug999511

bug 999511(cherry picked from commit 725a23802708eb70e3d7e8a2ce7179adbac806e4)
Bumping manifests a=b2g-bump