Use texture size to determine precision of texture coord varyings

src/gpu/gl/builders/GrGLProgramBuilder.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrGLProgramBuilder.h"
 #include "gl/GrGLProgram.h"
 #include "gl/GrGLSLPrettyPrint.h"
@@ skipping 395 matching lines @@
         if (0 != t) {
             suffixedVaryingName.append(varyingName);
             suffixedVaryingName.appendf("_%i", t);
             varyingName = suffixedVaryingName.c_str();
         }
 
         bool useLocalCoords = kLocal_GrCoordSet == processor->coordTransform(t).sourceCoords();
         const char* coords = useLocalCoords ? fVS.localCoords() : fVS.positionCoords();
 
         GrGLVertToFrag v(varyingType);
-        this->addCoordVarying(varyingName, &v, uniName, coords);
+        this->addVarying(varyingName, &v, processor->coordTransform(t).precision());
+        fCoordVaryings.push_back(TransformVarying(v, uniName, coords));
 
         SkASSERT(kVec2f_GrSLType == varyingType || kVec3f_GrSLType == varyingType);
         SkNEW_APPEND_TO_TARRAY(outCoords, GrGLProcessor::TransformedCoords,
                                (SkString(v.fsIn()), varyingType));
     }
 }
 
 void GrGLProgramBuilder::emitSamplers(const GrProcessor& processor,
                                       GrGLProcessor::TextureSamplerArray* outSamplers,
                                       GrGLInstalledProc* ip) {
@@ skipping 119 matching lines @@
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 GrGLInstalledFragProcs::~GrGLInstalledFragProcs() {
     int numProcs = fProcs.count();
     for (int e = 0; e < numProcs; ++e) {
         SkDELETE(fProcs[e]);
     }
 }