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

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https://hg.mozilla.org/integration/gaia-central/rev/87d53daa994c
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12895 from AlinT/test_import_contacts_from_sdcard

Bug 927348 - Write a test to import from VCF file on SD card

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https://hg.mozilla.org/integration/gaia-central/rev/0cd7fd53b13c
Author: AlinT <trifandreialin@gmail.com>
Desc: Bug 927348 - Write a test to import from VCF file on SD card
Bug 927493 - Fast-path for certified apps CSP r=geekboy