Some GrGLShaderBuilder cleanup

Review URL: https://codereview.appspot.com/6500043/



git-svn-id: http://skia.googlecode.com/svn/trunk@5322 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/effects/SkLightingImageFilter.cpp b/src/effects/SkLightingImageFilter.cpp
index c73e884..408e702 100644
--- a/src/effects/SkLightingImageFilter.cpp
+++ b/src/effects/SkLightingImageFilter.cpp
@@ -1148,7 +1148,7 @@
                           interiorNormalBody.c_str(),
                           &interiorNormalName);
 
-    code->appendf("\t\tvec2 coord = %s;\n", builder->fSampleCoords.c_str());
+    code->appendf("\t\tvec2 coord = %s;\n", builder->defaultTexCoordsName());
     code->appendf("\t\tfloat m[9];\n");
 
     const char* imgInc = builder->getUniformCStr(fImageIncrementUni);