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

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https://hg.mozilla.org/integration/gaia-central/rev/e6cdfbf454c6
Author: punamdahiya <punamdahiya@yahoo.com>
Desc: Merge pull request #21885 from giovannic/bugfix

Bug 1038984 - [L10n][Gallery] Clean up mozL10n.get uses in Gallery app

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https://hg.mozilla.org/integration/gaia-central/rev/86eaf6cf3528
Author: Giovanni Charles <giovanni.charles@gmail.com>
Desc: Bug 1038984 - [L10n][Gallery] Clean up mozL10n.get uses in Gallery app r=gandalf, pdahiya, dflanagan
Bumping manifests a=b2g-bump