Frameworks: speed up statubar/notification drawer

a lot user complain about slow statusbar pull down introduced
with jb 4.2....this speed it up

thanks to IceColdJelly

Change-Id: Iae108f5680b25ea995168a505a30e06bef0185d3
Remove useless/repetitive code

fixScale(float) method has been extracted from the code but the original
code has been kept in place. Because of this, the animation scale is
"fixed" twice which is not necessary. This patch, simply call
fixScale(float) once and stores the result of it in the scale variable.

Change-Id: I50aeacbc2c13ebbf447506ae4309d50c0e313837