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

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https://hg.mozilla.org/integration/gaia-central/rev/68851e1723ee
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #17025 from crdlc/bug-959211

Bug 959211 - [Download Manager] Manage stopped downloads and resuming th...

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https://hg.mozilla.org/integration/gaia-central/rev/a1093972278c
Author: crdlc <crdlc@tid.es>
Desc: Bug 959211 - [Download Manager] Manage stopped downloads and resuming them (offline -> online)
Bumping manifests a=b2g-bump