Method addRole

flow/Trace.cpp:538–544

	}

	void addRole(std::string const& role) {
		MutexHolder holder(mutex);

		RoleInfo& r = mutateRoleInfo();
		++r.roles[role];
		r.refreshRolesString();
	}

	void removeRole(std::string const& role) {
		MutexHolder holder(mutex);