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

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https://hg.mozilla.org/integration/gaia-central/rev/d5ee39aec632
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #21253 from steveck-chung/bug-1030160

Bug 1030160 - [Messages][MMS] Subject is considered empty even if it has several empty lines

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https://hg.mozilla.org/integration/gaia-central/rev/5b88abdd2d23
Author: Steve Chung <schung@mozilla.com>
Desc: Bug 1030160 - [Messages][MMS] Subject is considered empty (placeholder is displayed) even if it has several empty lines. r=julienw
Bumping manifests a=b2g-bump