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

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https://hg.mozilla.org/integration/gaia-central/rev/7cce35091212
Author: chirarobert <robert.chira@softvision.ro>
Desc: Merge pull request #26184 from viorelaioia/bug_1100256

Bug 1100256 - Unxfail test_browser_save_image.py, as Bug 1098338 is fixe...

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https://hg.mozilla.org/integration/gaia-central/rev/b10f4f0fb521
Author: Viorela Ioia <viorelaioia@gmail.com>
Desc: Bug 1100256 - Unxfail test_browser_save_image.py, as Bug 1098338 is fixed
Bumping manifests a=b2g-bump