Make SkImage::getTexture() const

src/image/SkImage.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkImageGenerator.h"
@@ skipping 37 matching lines @@
 
 bool SkImage::readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
                            int srcX, int srcY) const {
     SkReadPixelsRec rec(dstInfo, dstPixels, dstRowBytes, srcX, srcY);
     if (!rec.trim(this->width(), this->height())) {
         return false;
     }
     return as_IB(this)->onReadPixels(rec.fInfo, rec.fPixels, rec.fRowBytes, rec.fX, rec.fY);
 }
 
-GrTexture* SkImage::getTexture() {
+GrTexture* SkImage::getTexture() const {
     return as_IB(this)->onGetTexture();
 }
 
 SkShader* SkImage::newShader(SkShader::TileMode tileX,
                              SkShader::TileMode tileY,
                              const SkMatrix* localMatrix) const {
     return as_IB(this)->onNewShader(tileX, tileY, localMatrix);
 }
 
 SkData* SkImage::encode(SkImageEncoder::Type type, int quality) const {
@@ skipping 107 matching lines @@
     surface->getCanvas()->translate(-src.x(), -src.y());
 
     SkPaint paint;
     paint.setXfermodeMode(SkXfermode::kSrc_Mode);
     paint.setFilterQuality(quality);
     surface->getCanvas()->drawImage(this, 0, 0, &paint);
     return surface->newImageSnapshot();
 }