Bumping gaia.json for 1 gaia-central revision(s) a=gaia-bump

========

https://hg.mozilla.org/integration/gaia-central/rev/1145eee5bd62
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Bug 906549 - Set a background-size to handle images

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "28f428a7e8309fd8704332eaed5a79a9676dc9d3", 
+    "revision": "1145eee5bd62a8cc769d2c3d5f77516b8564d341", 
     "repo_path": "/integration/gaia-central"
 }