Fix text-as-path with skshader on gpu

[bsalomon, 2011-06-13 21:28:05]

Shaded text-as-path was broken in Gr because we lost our tweaks to the sampler
matrices (mult by inv VM) when switching back to .

Modifies the ShaderText sample/GM to draw text-on-path to exercise this path.

[reed1, 2011-06-13 21:41:26]

Suggesting a comment. LGTM

http://codereview.appspot.com/4576057/diff/4002/gpu/src/GrTextContext.cpp
File gpu/src/GrTextContext.cpp (right):

http://codereview.appspot.com/4576057/diff/4002/gpu/src/GrTextContext.cpp#new...
gpu/src/GrTextContext.cpp:117: 
/*
    We need to call preConcatMatrix with our viewmatrix's inverse, for each
texture and mask in the paint. However, computing the inverse can be expensive,
and its possible we may not have any textures or masks, so these two loops are
written such that we only compute the inverse (once) if we needed it.
*/

[bsalomon, 2011-06-13 21:56:02]

Checked in with comment at r1575