Remove extraneous const qualifier.

Remove extraneous const qualifier.

Found by clang:
[293/898] CXX obj/src/gpu/gl/gr.GrGpuGL.o
../../src/gpu/gl/GrGpuGL.cpp:2031:1: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
const GrGLenum tile_to_gl_wrap(SkShader::TileMode tm) {
        ^~~~~

Signed-off-by: Thiago Farina <tfarina@chromium.org>

[tfarina1, 2012-09-07 16:36:09]

I don't have commit rights, as you might know. ;)

So, when you approve, could you commit for me?

Thanks,

[bsalomon, 2012-09-07 16:54:43]

On 2012/09/07 16:36:09, tfarina1 wrote:
> I don't have commit rights, as you might know. ;)
> 
> So, when you approve, could you commit for me?
> 
> Thanks,

Thanks! LGTM. Committed as r5437.