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

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https://hg.mozilla.org/integration/gaia-central/rev/e07e3027a2fa
Author: gasolin <gasolin@gmail.com>
Desc: Merge pull request #12144 from mpizza/Bug_908846_tablet_wallpaper

Bug_908846 - Add New Wallpapers for 1.2 for Tablet, r=fred

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https://hg.mozilla.org/integration/gaia-central/rev/e7657e750f3e
Author: GaryChen(pychen) <mmm198219@gmail.com>
Desc: Bug_908846 - Add New Wallpapers for 1.2 for Tablet
    remove old images

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "8d832c25f38a02be7536b15d00f6757cb86db590", 
+    "revision": "e07e3027a2fa66a69a2ff6b01ef28e717cff7675", 
     "repo_path": "/integration/gaia-central"
 }