perform_step! refactor for Rosenbrock #3979

Job	Run time
test (InterfaceI, 1)	7m 53s
test (InterfaceII, 1)	6m 31s
test (InterfaceIII, 1)	6m 54s
test (Integrators_I, 1)	13m 50s
test (AlgConvergence_I, 1)	7m 8s
test (AlgConvergence_II, 1)	6m 4s
test (AlgConvergence_III, 1)	8m 36s
test (Downstream, 1)	13m 5s
test (ODEInterfaceRegression, 1)	8m 9s
test (Multithreading, 1)	10m 11s
test (OrdinaryDiffEqAdamsBashforthMoulton, 1)	7m 26s
test (OrdinaryDiffEqBDF, 1)	9m 42s
test (OrdinaryDiffEqCore, 1)	5m 45s
test (OrdinaryDiffEqDefault, 1)	6m 24s
test (OrdinaryDiffEqDifferentiation, 1)	5m 43s
test (OrdinaryDiffEqExplicitRK, 1)	6m 1s
test (OrdinaryDiffEqExponentialRK, 1)	8m 38s
test (OrdinaryDiffEqExtrapolation, 1)	8m 20s
test (OrdinaryDiffEqFIRK, 1)	7m 56s
test (OrdinaryDiffEqFeagin, 1)	8m 13s
test (OrdinaryDiffEqFunctionMap, 1)	5m 41s
test (OrdinaryDiffEqHighOrderRK, 1)	7m 0s
test (OrdinaryDiffEqIMEXMultistep, 1)	5m 46s
test (OrdinaryDiffEqLinear, 1)	8m 14s
test (OrdinaryDiffEqLowOrderRK, 1)	7m 26s
test (OrdinaryDiffEqLowStorageRK, 1)	13m 8s
test (OrdinaryDiffEqNordsieck, 1)	7m 8s
test (OrdinaryDiffEqPDIRK, 1)	5m 57s
test (OrdinaryDiffEqPRK, 1)	5m 55s
test (OrdinaryDiffEqQPRK, 1)	7m 10s
test (OrdinaryDiffEqRKN, 1)	8m 32s
test (OrdinaryDiffEqRosenbrock, 1)	8m 28s
test (OrdinaryDiffEqSDIRK, 1)	5m 49s
test (OrdinaryDiffEqSSPRK, 1)	9m 18s
test (OrdinaryDiffEqStabilizedIRK, 1)	6m 35s
test (OrdinaryDiffEqStabilizedRK, 1)	8m 2s
test (OrdinaryDiffEqSymplecticRK, 1)	14m 28s
test (OrdinaryDiffEqTsit5, 1)	5m 57s
test (OrdinaryDiffEqVerner, 1)	5m 50s
	5h 8m 53s

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