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

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https://hg.mozilla.org/integration/gaia-central/rev/fa99eccd1505
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Merge pull request #21500 from etiennesegonzac/bug-1027231

Bug 1027231 - Making sure windows' height are integers in device pixels. r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/77f0158c0b17
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Bug 1027231 - Making sure windows' height are integers in device pixels.
Bumping manifests a=b2g-bump
Bumping manifests a=b2g-bump