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

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https://hg.mozilla.org/integration/gaia-central/rev/ffd9b630adb7
Author: Rudy Lu <me@rudy.lu>
Desc: Merge pull request #23760 from RudyLu/keyboard/Bug1062571

Bug 1062571 - Keyboard is basically unusable with the new alternative chars menu.
r=timdream.

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https://hg.mozilla.org/integration/gaia-central/rev/a27701a86fc7
Author: Rudy Lu <me@rudy.lu>
Desc:  Bug 1062571 - Keyboard is basically unusable with the new "alternative
 chars menu" UI.
  - Should not cause JS error when invoking isMenuTarget() when there is
    no alternative chars menu.
Bumping manifests a=b2g-bump