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

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https://hg.mozilla.org/integration/gaia-1_3/rev/c065d0f56966
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #16576 from brendandahl/v1.3-uplift

Bug 966865 - Update gaia pdf.js to version 0.8.997.

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https://hg.mozilla.org/integration/gaia-1_3/rev/d15817a73848
Author: Brendan Dahl <brendan.dahl@gmail.com>
Desc: Bug 966865 - Update gaia pdf.js to version 0.8.997.
Bumping manifests a=b2g-bump