Bumping gaia.json for 2 gaia-central revision(s)

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https://hg.mozilla.org/integration/gaia-central/rev/59cd74709f7e
Author: Rudy Lu <left.lu@gmail.com>
Desc: Merge pull request #11040 from RudyLu/pdfjs/update_to_0.8.352

Bug 881152 - update pdf.js in Gaia to 0.8.352 for hdpi resolution suppor...
r=vingtetun

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https://hg.mozilla.org/integration/gaia-central/rev/1a7a4cb2fabe
Author: Rudy Lu <left.lu@gmail.com>
Desc: Bug 881152 - update pdf.js in Gaia to 0.8.352 for hdpi resolution support.