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

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https://hg.mozilla.org/integration/gaia-central/rev/1ec87089ac6d
Author: Ryan VanderMeulen <ryanvm@gmail.com>
Desc: Merge pull request #24379 from oklang/bug-1069791-Add-Firefox-OS-default-theme

Bug 1069791 - Add Firefox OS default theme.

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https://hg.mozilla.org/integration/gaia-central/rev/60aab5463e65
Author: Olle Klang <olle.klang@sonymobile.com>
Desc: Bug 1069791 - Add Firefox OS default theme.
Bumping manifests a=b2g-bump