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

========

https://hg.mozilla.org/integration/gaia-central/rev/175311ccd332
Author: Justin D'Arcangelo <justindarc@gmail.com>
Desc: Merge pull request #20378 from justindarc/bug1015385

Bug 1015385 - [Camera] Implement new startup loading events

========

https://hg.mozilla.org/integration/gaia-central/rev/3e868ef7f199
Author: Justin D'Arcangelo <justindarc@gmail.com>
Desc: Bug 1015385 - [Camera] Implement new startup loading events

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "1accc4295bbcf030e8de880f3d92018c5c620bbd", 
+    "revision": "175311ccd332f73c558d7ea0a4e929342b9137d6", 
     "repo_path": "/integration/gaia-central"
 }