fx2.2-graphics-scrum-h175: performance regression on Mac (initially 50% but now unknown)

There is up to 50% performance regression in fx2.2-graphics-scrum-h175 build on Mac.
It looks like this is because of "RT-17388 (Mac plugin support)" as
according to Hudson fx2.2-graphics-scrum-h175 build contains only this change.

The regressions are seen at least in:
 Controls.Buttons
 up to 75% in Controls.TextField
 up to 59% in Controls.TreeView-Expand
 up to 57% in DirtyArea
 up to 30% in FXFire
 up to 15% in GUIMark2.Text


Controls.Buttons show improvements, but this seems to be not true as it looks like fullspeed mode didn't work for
builds < h175 for some reason. I can see 40% regression when running Controls.Buttons on my Mac with h175 against h174.

I tried to run Controls.Buttons, DirtyArea and FXFire as well and can easy reproduce the regressions on my Mac.