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

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https://hg.mozilla.org/integration/gaia-central/rev/6946a71605af
Author: Mihai Cîrlănaru <mihai@cirlanaru.com>
Desc: Merge pull request #15505 from mihai/bug_937975

Bug 937975 - [Settings] Add title for USB storage confirm dialog, r=@crh0716

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https://hg.mozilla.org/integration/gaia-central/rev/4f1be5e6446c
Author: Mihai Cirlanaru <mihai@cirlanaru.com>
Desc: Bug 937975 - [Settings] Add title for USB storage confirm dialog. r=arthurcc

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "53a8a9a7b4edff4c4955b43833bc7e9c8916653e", 
+    "revision": "6946a71605af13e0284fb6f5bbe38aa4c05155d7", 
     "repo_path": "/integration/gaia-central"
 }