Snowball: X Video extension driver can’t work on 480p(854x480) yuv input mode.

[Fang Bao]

Description:
---------------
When I played media stream on snowball with latest Linaro 12.06 release image, I found that the Totem couldn’t play the 480p streams correctly. So I run the GStreamer tools to locate the root cause as follow command:

gst-launch videotestsrc ! video/x-raw-yuv, width=854, height=480 ! xvimagesink

The image of window is error. I had uploaded the screenshot via attachment.
For further information, I tried other different resolutions input with above commands. They are correct. Here is the summary:

320x240 OK
640x480 OK
854x480 Failed
1024x768 OK
1280x720 OK
1920x1080 OK

Since the xvimagesink plugin is based on X Video extension driver, I guess there might be a bug in it.

Hardware:
------------------
snowball V10
LCD, Dell E2011H (1024x768, HDMI/DVI)

Software:
------------------
Image URL : http://releases.linaro.org/12.06/ubuntu/leb-snowball/
Used dd tool to flash sd image to sdcard and insert it in snowball. After booting, upgrade system to latest status.