Merge branch 'stable-2.8' into stable-2.9

* stable-2.8:
  SideBySide2: Fix failure to load from "ISE EditIterator out of bounds"
  Remove "Click to" from topic edit button's tooltip
  Fix: wrongly throw 'commit already exists' exception
  Update sshd to 0.11.0
  Bump SSHD version to 0.10.1 and enable nio2 backend

Conflicts:
	gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Topic.ui.xml

Change-Id: I63c1e12bbd413a8e212de5b2a8cf71fa2a2ce52d