Minor cleanup FirefoxBinary.java

Signed-off-by: Andreas Tolfsen <ato@mozilla.com>
Use right annotation

Using the right annotation to force the compiler to keep the seemingly
no-op statement.  This fixes it for all compilation modes.

Signed-off-by: Andreas Tolfsen <ato@mozilla.com>
Allowing FindBy, FindBys, FindAll annotations on types

Helps building nested/modular PageObject structures.

Signed-off-by: Andreas Tolfsen <ato@mozilla.com>