Make GrGLSLPrimitiveProcessor::emitTransforms take local coords as GrShaderVar.

Also remove unused position variable parameter.

Change-Id: I37f98a03ac1ca750810de13b08e3ffa11e41828c
Reviewed-on: https://skia-review.googlesource.com/81320
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/ops/GrTextureOp.cpp b/src/gpu/ops/GrTextureOp.cpp
index f9600e5..79a22d8 100644
--- a/src/gpu/ops/GrTextureOp.cpp
+++ b/src/gpu/ops/GrTextureOp.cpp
@@ -107,8 +107,7 @@
                 this->emitTransforms(args.fVertBuilder,
                                      args.fVaryingHandler,
                                      args.fUniformHandler,
-                                     gpArgs->fPositionVar,
-                                     textureGP.fTextureCoords.fName,
+                                     textureGP.fTextureCoords.asShaderVar(),
                                      args.fFPCoordTransformHandler);
                 if (args.fShaderCaps->preferFlatInterpolation()) {
                     args.fVaryingHandler->addFlatPassThroughAttribute(&textureGP.fColors,