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

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https://hg.mozilla.org/integration/gaia-central/rev/42689e15ce61
Author: Yura Zenevich <yura.zenevich@gmail.com>
Desc: Merge pull request #21360 from yzen/bug-962434

Bug 962434 - Moving value selector into subcomponents of an appWindow. I...

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https://hg.mozilla.org/integration/gaia-central/rev/72f28b8f6b20
Author: Yura Zenevich <yzenevich@mozilla.com>
Desc: Bug 962434 - Moving value selector into subcomponents of an appWindow. Improving its visibility a11y. r=alive

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "3c184c41a10208a0ef1b6331c6d272685ddd973e", 
+    "revision": "42689e15ce6116948b185b9c848e14e8ad0234d6", 
     "repo_path": "/integration/gaia-central"
 }