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

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https://hg.mozilla.org/integration/gaia-central/rev/ecef4f8ef3cc
Author: steveck-chung <schung@mozilla.com>
Desc: Merge pull request #14762 from steveck-chung/incoming-call-slider-modulize

Bug 945096 - Re-implement locked call screen with canvas. r=etiennesegonzac, a=1.3 blocking+

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https://hg.mozilla.org/integration/gaia-central/rev/40c880d393af
Author: Steve Chung <schung@mozilla.com>
Desc: Bug 945096 - Re-implement locked call screen with canvas