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

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https://hg.mozilla.org/integration/gaia-central/rev/ad1884a1465c
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #25195 from KevinGrandon/bug_1033223_bookmark_test_intermittent

Bug 1033223 - [Vertical homescreen] Intermittent MarionetteJS failure on Travis: 1) Vertical - Bookmark Uninstall removal of bookmark: NoSuchElement: (7) Unable to locate element: gaia-confirm[data-type=remove]

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https://hg.mozilla.org/integration/gaia-central/rev/16f882b6a351
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1033223 - [Vertical homescreen] Intermittent MarionetteJS failure on Travis: 1) Vertical - Bookmark Uninstall removal of bookmark: NoSuchElement: (7) Unable to locate element: gaia-confirm[data-type=remove] r=kgrandon

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "cd6102d5b21510a135d58e58f3ada7e733833025", 
+    "revision": "ad1884a1465c7c790b449acc352de553d868548b", 
     "repo_path": "/integration/gaia-central"
 }