gallery: use inJustDecodeBounds in ImageFilterBorder

To avoid OOM exceptions loading the border drawable

JIRA: BUGDUMP-20716
https://jira.cyanogenmod.org/browse/BUGDUMP-20716
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>

Change-Id: Ie3fdb34de83f4a863c0d1d23bb8162b2425955e9