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

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https://hg.mozilla.org/integration/gaia-central/rev/d266560b990b
Author: Jonathan Griffin <jgriffin@mozilla.com>
Desc: Merge pull request #10990 from jonallengriffin/disablebusytime

Bug 893248 - Disable busytime_test.js for near perma-orange in TBPL, a=t...

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https://hg.mozilla.org/integration/gaia-central/rev/f42afb0f2a73
Author: Jonathan Griffin <jgriffin@mozilla.com>
Desc: Bug 893248 - Disable busytime_test.js for near perma-orange in TBPL, a=test-only

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "9a8405332100cc0e4223058978a5cc444baa5120", 
+    "revision": "d266560b990b5c4fe6055c30873b97f7f75765f0", 
     "repo_path": "/integration/gaia-central"
 }