Fix Linux texture format in SampleApp

SampleApp builds skia on Linux with BGRA pixel order, but Ganesh's SampleApp assumes GL_RGBA texture format on all platforms except Windows (where it uses GL_BGRA), so texture colours come out wrong.  As a temporary fix, do on Linux what we do on Windows, and assume GL_BGRA.  (This should be made more general later, and the assumption of matching formats between Skia and Ganesh removed.)

[Stephen White, 2011-05-04 19:58:59]

Whoops; upload the correct patch this time

[bsalomon, 2011-05-04 20:06:12]

LGTM
On 2011/05/04 19:58:59, Stephen White wrote:
> Whoops; upload the correct patch this time

[Stephen White, 2011-05-04 20:13:12]

Landed as http://code.google.com/p/skia/source/detail?r=1247; closing.