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

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https://hg.mozilla.org/integration/gaia-central/rev/87fa9c9b376b
Author: Florin Strugariu <bebef_1987@yahoo.com>
Desc: Merge pull request #19892 from yzen/bug-1018214

Bug 1018214 - adding a number of gaia ui tests for status bar and utilit...

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https://hg.mozilla.org/integration/gaia-central/rev/506220dedd86
Author: Yura Zenevich <yzenevich@mozilla.com>
Desc: Bug 1018214 - adding a number of gaia ui tests for status bar and utility tray accessibility. r=Bebe

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "226c39e34bea8e57e3f75a6e9c884b722e34beb5", 
+    "revision": "87fa9c9b376bed8c5f923c1a95873a3df26297df", 
     "repo_path": "/integration/gaia-central"
 }