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

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https://hg.mozilla.org/integration/gaia-central/rev/b0db64aea806
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #16798 from julienw/974733-sending-sms-activity-v2

Bug 974733 - [Sora][Message]The conversation message display wrong after...

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https://hg.mozilla.org/integration/gaia-central/rev/740ccb66664a
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 974733 - [Sora][Message] We should not change panels when handling the "sending" event on the window that does not send the message r=schung

When the user presses the "send" button, we set a boolean, so
that when we receive the "sending" event, we know whether we're in the same
window.
Bumping manifests a=b2g-bump