Create special surfaces according to original device (not always in N32)

src/effects/SkXfermodeImageFilter.cpp

 /*
  * Copyright 2013 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkXfermodeImageFilter.h"
 
 #include "SkCanvas.h"
@@ skipping 77 matching lines @@
 
 #if SK_SUPPORT_GPU
     if (source->isTextureBacked()) {
         return this->filterImageGPU(source,
                                     background, backgroundOffset, 
                                     foreground, foregroundOffset,
                                     bounds);
     }
 #endif
 
-    const SkImageInfo info = SkImageInfo::MakeN32(bounds.width(), bounds.height(),
-                                                  kPremul_SkAlphaType);
-    sk_sp<SkSpecialSurface> surf(source->makeSurface(info));
+    sk_sp<SkSpecialSurface> surf(source->makeSurface(bounds));
     if (!surf) {
         return nullptr;
     }
 
     SkCanvas* canvas = surf->getCanvas();
     SkASSERT(canvas);
 
     canvas->clear(0x0); // can't count on background to fully clear the background
 
     canvas->translate(SkIntToScalar(-bounds.left()), SkIntToScalar(-bounds.top()));
@@ skipping 143 matching lines @@
     matrix.setTranslate(SkIntToScalar(-bounds.left()), SkIntToScalar(-bounds.top()));
     drawContext->drawRect(GrNoClip(), paint, matrix, SkRect::Make(bounds));
 
     return SkSpecialImage::MakeFromGpu(SkIRect::MakeWH(bounds.width(), bounds.height()),
                                        kNeedNewImageUniqueID_SpecialImage,
                                        drawContext->asTexture(),
                                        sk_ref_sp(drawContext->getColorSpace()));
 }
 
 #endif