There are some differences in width handling between the browsers used
to run the tests, most likely due to their support (or lack of) of
certain CSS features: PhantomJS requires "width" to be set (probably
because it does not handle flex displays and treats it like a block, so
"min-width" does not matter in this case), while Firefox requires
"min-width" to be set (otherwise the children of "#controls" could be
compressed due to its use of flex display and the elements would end
with a different width than the one needed for the tests). Due to all
that the width of the breadcrumb siblings must be specified in the tests
using both "width" and "min-width".
Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>