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

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https://hg.mozilla.org/integration/gaia-central/rev/d7ff1015ccee
Author: Rex KM Lee <rexboy@mozilla.com>
Desc: Merge pull request #11270 from rexboy7/fix-bug899511

Bug 899501 - [Dialer] Layout adjusting for HD support on suggestion over...

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https://hg.mozilla.org/integration/gaia-central/rev/fc83b598b958
Author: Rex Lee <rexboy@mozilla.com>
Desc: Bug 899501 - [Dialer] Layout adjusting for HD support on suggestion overlay

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "a6b81f7d4b84287a2bdf0ce78df08fed9fd46bee", 
+    "revision": "d7ff1015ccee68bc68364f589e4eb42d1130a493", 
     "repo_path": "/integration/gaia-central"
 }