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

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https://hg.mozilla.org/integration/gaia-central/rev/a36df4782c67
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #11189 from crh0716/898937

Bug 898937 - Add background size to the thumb r=rexboy

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https://hg.mozilla.org/integration/gaia-central/rev/591a4783221c
Author: crh0716 <crh0716@gmail.com>
Desc: Bug 898937 - Add background size to the thumb

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "bb821fbbbdd5bad1c11317fb7bf7116162aa50b1", 
+    "revision": "a36df4782c679df0ccb69a3472fb0b414f5ff7a7", 
     "repo_path": "/integration/gaia-central"
 }