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

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https://hg.mozilla.org/integration/gaia-central/rev/d15738b957db
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #22346 from snowmantw/issue1041889

Bug 1041889 - [Browser] After the lockscreen orientation change does not...

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https://hg.mozilla.org/integration/gaia-central/rev/ad049380e791
Author: Greg Weng <snowmantw@gmail.com>
Desc: Bug 1041889 - [Browser] After the lockscreen orientation change does not occur

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "2bf6819ac166e72cccdd48ff6f39d6f0c0e7fc15", 
+    "revision": "d15738b957db6f7e43164e89e19e79ed5901d750", 
     "repo_path": "/integration/gaia-central"
 }