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

========

https://hg.mozilla.org/integration/gaia-central/rev/18c3b948728e
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Merge pull request #22914 from pivanov/bug-1035680

Bug 1035680 - [FTU] - check missing images

========

https://hg.mozilla.org/integration/gaia-central/rev/fb881bfc2318
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Bug 1035680 - [FTU] - check missing images

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "3f84cc0571ef3e0b41b3b57c9afd37802d59599c", 
+    "revision": "18c3b948728e9ae13da0128e4e0db1918f3564c4", 
     "repo_path": "/integration/gaia-central"
 }