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

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https://hg.mozilla.org/integration/gaia-central/rev/446e8e49d9f8
Author: autolander <bug.autolander@gmail.com>
Desc: Bug 1082993 - merge pull request #25261 from gasolin:issue-1082993 to mozilla-b2g:master

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https://hg.mozilla.org/integration/gaia-central/rev/2c038ca592de
Author: gasolin <gasolin@gmail.com>
Desc: Bug 1082993 - [settings] refactor Developer panel with AMD pattern +autoland
Bumping manifests a=b2g-bump