Merged r8571, r8572, r8573, r8574, r8578, r8582, r8588, r8589 from trunk
Arabic translations (#9943).
recovery copyright statement in Arabic calendar JavaScript (#9943)
fix Arabic JavaScript variable name (#9943)
remove trailing white-spaces from config/locales/es.yml
remove trailing white-spaces from config/locales/en-GB.yml
remove trailing white-spaces from config/locales/el.yml
remove trailing white-spaces from config/locales/de.yml
remove trailing white-spaces from config/locales/da.yml
remove trailing white-spaces from config/locales/ar.yml
remove trailing white-spaces from config/locales/cs.yml