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

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https://hg.mozilla.org/integration/gaia-central/rev/5e371d8512e6
Author: Yoshi Huang <allstars.chh@mozilla.com>
Desc: Merge pull request #18655 from kamituel/Bug_997338_3

Bug 997333: Fixed comments. Added null-check in fromUTF8(). r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/8cec82b07280
Author: kamituel <kamituel@gmail.com>
Desc: Bug 997338 - Fixed comments and null-check in fromUTF8().
Bumping manifests a=b2g-bump