Bumping gaia.json for 4 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/d9799704c001
Author: Douglas Sherk <github@sherk.me>
Desc: Merge pull request #18189 from DouglasSherk/994818-stickyheader-async

Bug 994818 - Make StickyHeader dispatch async refreshes, prevent thrashing. r=vingtetun

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https://hg.mozilla.org/integration/gaia-central/rev/fb6bbee8113f
Author: DouglasSherk <github@sherk.me>
Desc: Bug 994818 - Make StickyHeader dispatch async refreshes, prevent thrashing. r=vingtetun

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https://hg.mozilla.org/integration/gaia-central/rev/46e6b26169d0
Author: Yoshi Huang <allstars.chh@mozilla.com>
Desc: Merge pull request #18056 from svic/Bug_988254

Bug 988254 - Proper initialization in Handover Manager if BT is already enabled at boot. r=evelyn

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https://hg.mozilla.org/integration/gaia-central/rev/4ed016d190af
Author: Arno Puder <arno@puder.org>
Desc: Bug 988254 - Proper initialization in Handover Manager if BT is already enabled at boot
Bumping manifests a=b2g-bump