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

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https://hg.mozilla.org/integration/gaia-1_4/rev/62aa0e6dcf46
Author: Eric Chou <echou@mozilla.com>
Desc: Merge pull request #14353 from eric30/Bug-945631

Bug 945631 - Listen to event discoverystatechanged, r=arthurcc

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https://hg.mozilla.org/integration/gaia-1_4/rev/fbda7949db89
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #18152 from alivedise/bugzilla/825435/dupe-alert

Bug 994537 - Fix dupe alert, r=timdream
Bumping manifests a=b2g-bump