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

========

https://hg.mozilla.org/integration/gaia-central/rev/5de9f5b9b2f8
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #11639 from julienw/fix-travis-2

Bug 905775 - Firefox is failing silently in recent travis builds during `make test-agent-test` step
r=ochameau

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https://hg.mozilla.org/integration/gaia-central/rev/538469b832ad
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 905775 - Firefox is failing silently in recent travis builds during `make test-agent-test` step

This turns off the desktop extensions for the tests, and enabled the touch
events in DEBUG mode, so that the tests can actually use touch events.

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "4cfbd89887bd8f8453bb7c5906f75086b974c97f", 
+    "revision": "5de9f5b9b2f843825f13bd3667dc0fbf2e04e5f3", 
     "repo_path": "/integration/gaia-central"
 }