lib-manipulation/src/main/java/com/nhaarman/listviewanimations/itemmanipulation/dragdrop/HoverDrawable.java
void shift(final int height) {
        int shiftSize = isMovingUpwards() ? -height : height;
        mOriginalY += shiftSize;
        mDownY += shiftSize;
    }
void shift(final int height) {
        int shiftSize = isMovingUpwards() ? -height : height;
        mOriginalY += shiftSize;
        mDownY += shiftSize;
    }
Shifts the original y coordinates of this {@code HoverDrawable} {code height} pixels upwards or downwards,
depending on the move direction.

@param height the number of pixels this {@code HoverDrawable} should be moved. Should be positive.