'Generate and return a description of a build step.
|verb| is the short summary, e.g. ACTION or RULE.
|message| is a hand-written description, or None if not available.
|fallback| is the gyp-level name of the step, usable as a fallback.'

def GenerateDescription(self, verb, message, fallback):

    if (self.toolset != 'target'):
        verb += ('(%s)' % self.toolset)
    if message:
        return ('%s    %s' % (verb, self.ExpandSpecial(message)))
    else:
        return ('%s    %s:    %s' % (verb, self.name, fallback))
