Blender Git Loki

Fix T74927: Slow playback using Auto Normalization

Caused by rBedb3b7a323a1.

Using evaluate_fcurve_only_curve actually causes quite a bit of slowdown
[6x] compared to bezier forward differencing [which was used prior to
rBedb3b7a323a1]. But full fcurve evaluation is desired with Dynamic
Interpolation Effects [Back/Elastic] since their min/max will not be
captured with forward differencing.

So now gain back speed [using bezier forward differencing] and only do
the full fcurve evaluation for dynamic interpolation effects.

Maniphest Tasks: T74927

Differential Revision: https://developer.blender.org/D7196