Refactored CSSPropertyHandlerLazyProviderImpl#getHandlerClassName() as
the only client of this utility method to inline the simple logic and
mark the method deprecated. Add test case to for the
getHandlerClassName() method.

Change-Id: I6878ae9676ee7c62f27935e36f378012c0feb889
Signed-off-by: Karsten Thoms <karsten.thoms@itemis.de>