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

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https://hg.mozilla.org/integration/gaia-1_4/rev/4b7e99883335
Author: gasolin <gasolin@gmail.com>
Desc: Merge pull request #19658 from gasolin/issue-1011611-2

Issue 1011611 - disable share button before the activity is complete, r=dale

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https://hg.mozilla.org/integration/gaia-1_4/rev/59807d10acd1
Author: gasolin <gasolin@gmail.com>
Desc: Bug 1011611 - disable share button before the activity is complete
Bumping manifests a=b2g-bump