Merge changes from origin/7.1

3229847 Fix lost focus in Table when refreshing row cache (#12231)
654d570 Don't close an unbound VaadinSession for GAEVaadinServlet (#12209)
2ea19f3 Make VaadinService.closeInactiveUIs set UI threadlocals (#12186)
7f5a0a7 Add Require-Bundle for our rebased atmosphere bundle (#12195)

Change-Id: I65c9a33462b3508b763115f8410fec3e62e16d45

diff --cc server/src/com/vaadin/server/VaadinService.java
Simple merge

diff --cc server/src/com/vaadin/ui/UI.java
Simple merge