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

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https://hg.mozilla.org/integration/gaia-central/rev/373ab3009a8a
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Merge pull request #12157 from dominickuo/bug-838008

Bug 838008 - [email] Enable picking video and audio files as attachment, r=@asutherland

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https://hg.mozilla.org/integration/gaia-central/rev/0dda4bce72b7
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Bug 838008 - [email] Enable picking video and audio files as attachment

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "44b5d39b37b1e0e07e09953f52d176f687f15018", 
+    "revision": "373ab3009a8ab268dfea6c36482232e4ccdbc979", 
     "repo_path": "/integration/gaia-central"
 }