remove unused (by the outside) SkImage::newSurface, and simplify newImage -> newSubset

gm/image_pict.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 #include "SkCanvas.h"
 #include "SkImage.h"
@@ skipping 308 matching lines @@
             SkRect r = SkRect::MakeXYWH(x, y, SkIntToScalar(cache->info().width()),
                                         SkIntToScalar(cache->info().width()));
             canvas->drawRect(r, paint);
             canvas->drawLine(r.left(), r.top(), r.right(), r.bottom(), paint);
             canvas->drawLine(r.left(), r.bottom(), r.right(), r.top(), paint);
             return;
         }
         // No API to draw a GrTexture directly, so we cheat and create a private image subclass
         SkAutoTUnref<SkImage> image(new SkImage_Gpu(cache->info().width(), cache->info().height(),
                                                     cache->uniqueID(), kPremul_SkAlphaType, texture,
-                                                    0, SkSurface::kNo_Budgeted));
+                                                    SkSurface::kNo_Budgeted));
         canvas->drawImage(image, x, y);
 #endif
     }
 
     void drawSet(SkCanvas* canvas) const {
         SkMatrix matrix = SkMatrix::MakeTrans(-100, -100);
         canvas->drawPicture(fPicture, &matrix, nullptr);
 
         // Draw the tex first, so it doesn't hit a lucky cache from the raster version. This
         // way we also can force the generateTexture call.
@@ skipping 30 matching lines @@
 };
 DEF_GM( return new ImageCacheratorGM("picture", make_pic_generator); )
 DEF_GM( return new ImageCacheratorGM("raster", make_ras_generator); )
 DEF_GM( return new ImageCacheratorGM("ctable", make_ctable_generator); )
 #if SK_SUPPORT_GPU
     DEF_GM( return new ImageCacheratorGM("texture", make_tex_generator); )
 #endif