Set TimeZone for CalendarView Bitmaps

The generated and reference bitmaps wouldn't match, because the
emulator used a different timezone than device used to create
the reference images. Set the time zone before inflating the
view to use the same timezone all the time.

Add a prepare method to LayoutModifier in case other widgets
may need special action. Didn't bother adding a tearDown
method...because I didn't think it was necessary...

Change-Id: I5bac0620f49ef40d96ccb8c15f905ed33ba797e3