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

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https://hg.mozilla.org/integration/gaia-central/rev/5033338df80e
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #26754 from davidflanagan/bug1096839

Bug 1096839: add BMP support to shared/js/media/image_size.js to fix Gal... r=pdahiya

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https://hg.mozilla.org/integration/gaia-central/rev/aa8ff84f92e2
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Bug 1096839: add BMP support to shared/js/media/image_size.js to fix Gallery open activity

remove the now unused MAX_FILE_SIZE variable
Bumping manifests a=b2g-bump