Move canvas->surface association to the device subclasses

src/core/SkBitmapDevice.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapDevice.h"
 #include "SkConfig8888.h"
 #include "SkDeviceProperties.h"
@@ skipping 51 matching lines @@
     SkASSERT(valid_for_bitmap_device(bitmap.info(), NULL));
 }
 
 SkBitmapDevice::SkBitmapDevice(const SkBitmap& bitmap, const SkDeviceProperties& deviceProperties)
     : SkBaseDevice(deviceProperties)
     , fBitmap(bitmap)
 {
     SkASSERT(valid_for_bitmap_device(bitmap.info(), NULL));
 }
 
-SkBitmapDevice* SkBitmapDevice::Create(const SkImageInfo& origInfo,
-                                       const SkDeviceProperties* props) {
+bool SkBitmapDevice::CreateBackendBitmap(const SkImageInfo& origInfo, SkBitmap* target) {
     SkAlphaType newAT = origInfo.alphaType();
     if (!valid_for_bitmap_device(origInfo, &newAT)) {
-        return NULL;
+        return false;
     }
 
     const SkImageInfo info = origInfo.makeAlphaType(newAT);
     SkBitmap bitmap;
 
     if (kUnknown_SkColorType == info.colorType()) {
         if (!bitmap.setInfo(info)) {
-            return NULL;
+            return false;
         }
     } else {
         if (!bitmap.tryAllocPixels(info)) {
-            return NULL;
+            return false;
         }
         if (!bitmap.info().isOpaque()) {
             bitmap.eraseColor(SK_ColorTRANSPARENT);
         }
     }
+    target->swap(bitmap);
+    return true;
+}
 
+SkBitmapDevice* SkBitmapDevice::Create(const SkImageInfo& info,
+                                       const SkDeviceProperties* props) {
+    SkBitmap bitmap;
+    if (!CreateBackendBitmap(info, &bitmap)) {
+        return NULL;
+    }
     if (props) {
         return SkNEW_ARGS(SkBitmapDevice, (bitmap, *props));
     } else {
         return SkNEW_ARGS(SkBitmapDevice, (bitmap));
     }
 }
 
 SkImageInfo SkBitmapDevice::imageInfo() const {
     return fBitmap.info();
 }
 
-void SkBitmapDevice::replaceBitmapBackendForRasterSurface(const SkBitmap& bm) {
+void SkBitmapDevice::replaceBitmapBackend(const SkBitmap& bm) {
     SkASSERT(bm.width() == fBitmap.width());
     SkASSERT(bm.height() == fBitmap.height());
     fBitmap = bm;   // intent is to use bm's pixelRef (and rowbytes/config)
     fBitmap.lockPixels();
 }
 
 SkBaseDevice* SkBitmapDevice::onCreateCompatibleDevice(const CreateInfo& cinfo) {
     SkDeviceProperties leaky(cinfo.fPixelGeometry);
     return SkBitmapDevice::Create(cinfo.fInfo, &leaky);
 }
@@ skipping 266 matching lines @@
         paint.getRasterizer() ||
         paint.getPathEffect() ||
         paint.isFakeBoldText() ||
         paint.getStyle() != SkPaint::kFill_Style ||
         !SkXfermode::IsMode(paint.getXfermode(), SkXfermode::kSrcOver_Mode))
     {
         return true;
     }
     return false;
 }