Merge branch 'stable-2.6'

* stable-2.6:
  Reduce DOM nodes when updating reviewed status
  Fix PatchScreen leak when moving between files
  Use try/finally to ensure oldValue is cleared
  Remove unused HasValueChangeHandlers from PatchScriptSettingsPanel
  Make ListenableAccountDiffPreference final in PatchScriptSettingsPanel
  Remove unused setPreferences method on PatchTable
  init: Guess JDBC driver class if not configured