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

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https://hg.mozilla.org/integration/gaia-1_4/rev/6fb359350e36
Author: Justin D'Arcangelo <justindarc@gmail.com>
Desc: Merge pull request #20446 from justindarc/bug1014955-v1.4

Bug 1014955 - [Camera] Migrate v1.3T downsampling patches to v1.4/master

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https://hg.mozilla.org/integration/gaia-1_4/rev/a23053cceeca
Author: Justin D'Arcangelo <justindarc@gmail.com>
Desc: Bug 1014955 - [Camera] Migrate v1.3T downsampling patches to v1.4/master
Bumping manifests a=b2g-bump