'Verifies that the element identified by `locator` is visible.
Herein, visible means that the element is logically visible, not optically
visible in the current browser viewport. For example, an element that carries
display:none is not logically visible, so using this keyword on that element
would fail.
`message` can be used to override the default error message.
Key attributes for arbitrary elements are `id` and `name`. See
`introduction` for details about locating elements.'

@keyword
def element_should_be_visible(self, locator, message=''):

    self.info(("Verifying    element    '%s'    is    visible." % locator))
    visible = self.is_visible(locator)
    if (not visible):
        if (not message):
            message = ("The    element    '%s'    should    be    visible,    but    it    is    not." % locator)
        raise AssertionError(message)
