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

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https://hg.mozilla.org/integration/gaia-1_4/rev/186a1b807c4c
Author: GaryChen, PYChen, Gary <mmm198219@gmail.com>
Desc: Merge pull request #22356 from mpizza/v1.4_995148_add_patch

Bug 995148 - [Tarako][Gallery] Gallery exits when loading some specific pictures. uplift patch from v1.3 because Bug 1041853 need this patch.

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https://hg.mozilla.org/integration/gaia-1_4/rev/39fae24370b6
Author: John Hu <johu@mozilla.com>
Desc: Bug 995148 - [Tarako][Gallery] Gallery exits when loading some specific pictures
Bumping manifests a=b2g-bump