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

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https://hg.mozilla.org/integration/gaia-central/rev/6434a9e432b5
Author: Arnau <arnau@arnaumarch.com>
Desc: Merge pull request #14410 from rnowm/946718

Bug 946718 - [SMS] When there's no messages, the header shows a shadow below

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https://hg.mozilla.org/integration/gaia-central/rev/30b0978059d5
Author: rnowm <arnau@arnaumarch.com>
Desc: Bug 946718 - [SMS] When there's no messages, the header shows a shadow below

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "5df50375c3c773fe94f7ffb3150f5a4e1e1c6144", 
+    "revision": "6434a9e432b59dd3f7adb38d625031a65646b03b", 
     "repo_path": "/integration/gaia-central"
 }