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

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https://hg.mozilla.org/integration/gaia-1_4/rev/96f7a3742e0a
Author: russnicoletti <rnicoletti@mozilla.com>
Desc: Merge pull request #21239 from russnicoletti/bug-1028835_v1.4

Bug 1028835 - [dolphin][flame] video list display abnormal for a while when changing orientation

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https://hg.mozilla.org/integration/gaia-1_4/rev/6844d882a00a
Author: Russ Nicoletti <rnicoletti@mozilla.com>
Desc: Bug 1028835 - [dolphin][flame] video list display abnormal for a while when switch between landscape mode and portrait mode
Bumping manifests a=b2g-bump