Trebuchet: set default drawer scrolling effect to none

Stack was used for the ICS/JB/KK style app drawer,
the Lollipop styled drawer doesn't use scrolling effects.

Change-Id: Ied5e67ec2b3996a63ce870f206b47579d09897b1
Trebuchet: Further adjustment of panel overview glitch fix

 * These values takes care of the glitch also on HDPI devices.

Change-Id: Ia901699351ed887a9100bbec6d10be9e92b50c14