Removed toolbarlabel's set/removeFocus

toolbarlabel's set/removeFocus methods have become obsolete after converting the toolbar label
to a widget and after no more DOM replacing is being performed when changing a button's state.

Change-Id: Ibdca1cbd03e25e5b5878f4290fc40d2f3d25dc31
Merge "Removed toolbarlabel's set/removeFocus"