Generate a buildbot mail message and return a dictionary
           containing the message body, type and subject.

def formatMessageForBuildResults(self, mode, buildername, buildset, build, master, previous_results, blamelist):
        """Generate a buildbot mail message and return a dictionary
           containing the message body, type and subject."""
        ss_list = buildset['sourcestamps']
        results = build['results']

        ctx = dict(results=build['results'],
                   mode=mode,
                   buildername=buildername,
                   workername=build['properties'].get(
                       'workername', ["<unknown>"])[0],
                   buildset=buildset,
                   build=build,
                   projects=self.getProjects(ss_list, master),
                   previous_results=previous_results,
                   status_detected=self.getDetectedStatus(
                       mode, results, previous_results),
                   build_url=utils.getURLForBuild(
                       master, build['builder']['builderid'], build['number']),
                   buildbot_url=master.config.buildbotURL,
                   blamelist=blamelist,
                   summary=self.messageSummary(build, results),
                   sourcestamps=self.messageSourceStamps(ss_list)
                   )
        yield self.buildAdditionalContext(master, ctx)
        msgdict = self.renderMessage(ctx)
        return msgdict