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

========

https://hg.mozilla.org/integration/gaia-central/rev/9006e51d8ffd
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #24167 from julienw/1069238-fix-calendar-tests

Bug 1069238 - [Calendar] Failing unit test with newer mocha r=kgrandon

========

https://hg.mozilla.org/integration/gaia-central/rev/d113464207da
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 1069238 - [Calendar] Failing unit test with newer mocha r=kgrandon

========

https://hg.mozilla.org/integration/gaia-central/rev/bd499b5d0969
Author: Michael Wu <mwu@mozilla.com>
Desc: Merge pull request #24116 from michaelwu/bug-1022728-gaia

Bug 1022728 - Create a pref only build target

========

https://hg.mozilla.org/integration/gaia-central/rev/0865319c4b16
Author: Michael Wu <mwu@mozilla.com>
Desc: Bug 1022728 - Create a pref only build target
Bumping manifests a=b2g-bump