Although I will say that either it ought to be brought back, or the documentation ought to be updated regarding this, and ought to explain how to recreate all four kinds of flip-flops using registers. The only one that's immediately obvious is the D flip-flop; and even still, registers...
Flip-Flops and Latches / 18 1.9 Synchronous Logic / 21 1.10 Synchronous Timing Analysis / 23 1.11 Clock Skew / 25 1.12 Clock Jitter / 27 1.13 Derived Logical Building Blocks / 28 Chapter 2 Integrated Circuits and the 7400 Logic Families. . . . . . . . . . . . . . . . . . ...