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

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https://hg.mozilla.org/integration/gaia-central/rev/59f2cc603997
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #17741 from weideng/bug960946

Bug 960946 - [Keyboard] Change to the new sendKey API

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https://hg.mozilla.org/integration/gaia-central/rev/e7688d46cebd
Author: wdeng <wdeng@mozilla.com>
Desc: Bug 960946 - [Keyboard] Change to the new sendKey API
Bumping manifests a=b2g-bump