Fix Weird floating "add language" item

- Base theme has android:clipToPadding=false attribute. It let user
UI draw under navigation bar but also cause this problem. Add
android:clipToPadding=true in layout to fix the problem.

Fixes: 142108980
Test: manual
Change-Id: Ibe60b348a3c7c01d9786612ceac23a47a78a208a