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

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https://hg.mozilla.org/integration/gaia-central/rev/ca499c17e26a
Author: gitmai <mri@tid.es>
Desc: Merge pull request #15343 from gitmai/bug-958334-Usage-shows-NaN

Bug 958334 -[Usage] Mobile and Wi-Fi usage sometimes shows as NaN
r=salva

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https://hg.mozilla.org/integration/gaia-central/rev/fe5369929142
Author: mai <mri@tid.es>
Desc: Bug 958334 -[Usage] Mobile and Wi-Fi usage sometimes shows as NaN
Bumping manifests a=b2g-bump