Bumping gaia.json for 4 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/3ca26501ca9f
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #16958 from bebef1987/remove_dirs

Bug 947153 - Make travis install script clean up the b2g/ and profile/ d...

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https://hg.mozilla.org/integration/gaia-central/rev/d428c94e426b
Author: Bebe <bebe@mozilla.ro>
Desc: Bug 947153 - Make travis install script clean up the b2g/ and profile/ directories to aid local running

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https://hg.mozilla.org/integration/gaia-central/rev/f513fda75472
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #16989 from julienw/980981-fail-early-mocks-helper

Bug 980981 - [MocksHelper] Fail when we specify a mock twice r=rik

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https://hg.mozilla.org/integration/gaia-central/rev/403866c52a18
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 980981 - [MocksHelper] Fail when we specify a mock twice r=rik
Bumping manifests a=b2g-bump