Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_4/rev/9a1fec206688
Author: steveck-chung <schung@mozilla.com>
Desc: Merge pull request #18363 from steveck-chung/bug-992233

Bug 992233 - 984153 regressed the background color for suggestions list. r=julienw(cherry picked from commit 559c4b4d8bf5bfeb5c6ad7a22ddcf01949f15c74)

Conflicts:

	build/csslint/xfail.list
Bumping manifests a=b2g-bump