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

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https://hg.mozilla.org/integration/gaia-central/rev/0818ccb401e7
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #16353 from snowmantw/issue973501

Bug 973501 - [LockScreen] Fix undefined "lockScreen" and "LockScreen"

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https://hg.mozilla.org/integration/gaia-central/rev/2754ec8d427a
Author: Greg Weng <snowmantw@gmail.com>
Desc: Bug 973501 - [LockScreen] Fix undefined "lockScreen" and "LockScreen"

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "d57bb057f63dc1be85120c7305763cc495644608", 
+    "revision": "0818ccb401e793689adda5b6253e52fdeccba2f9", 
     "repo_path": "/integration/gaia-central"
 }