Bumping gaia.json for 6 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/e20a5ed7dac3
Author: Aleh Zasypkin <aleh.zasypkin@gmail.com>
Desc: Merge pull request #22948 from azasypkin/bug-1053964-activity-test

Bug 1053964 - [Messages][Tests] Add marionette JS test case to verify close\back button behaviour when app is in activity mode. r=julien, schung

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https://hg.mozilla.org/integration/gaia-central/rev/a16c2e02c31b
Author: Aleh Zasypkin <azasypkin@mozilla.com>
Desc: Bug 1053964 - [Messages][Tests] Add marionette JS test case to verify close\back button behaviour when app is in activity mode. r=schung, julien

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https://hg.mozilla.org/integration/gaia-central/rev/b61e27139a9c
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #23689 from ehsan/1062569

Bug 1062569 - Inline the activity options used in the wappush app in order to make it easier to automatically extract the activity arguments from the source code

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https://hg.mozilla.org/integration/gaia-central/rev/f18e1e438519
Author: Ehsan Akhgari <ehsan@mozilla.com>
Desc: Bug 1062569 - Inline the activity options used in the wappush app in order to make it easier to automatically extract the activity arguments from the source code; r=timdream

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https://hg.mozilla.org/integration/gaia-central/rev/3b4e3b7150fd
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #23687 from ehsan/1062568

Bug 1062568 - Inline the activity options used in the system app in order to make it easier to automatically extract the activity arguments from the source code

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https://hg.mozilla.org/integration/gaia-central/rev/ce23e3fea93f
Author: Ehsan Akhgari <ehsan@mozilla.com>
Desc: Bug 1062568 - Inline the activity options used in the system app in order to make it easier to automatically extract the activity arguments from the source code; r=timdream
Bumping manifests a=b2g-bump