use SkImageInfo directly, instead of converting to SkBitmap::Config

src/image/SkSurface.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 "SkSurface_Base.h"
 #include "SkImagePriv.h"
 #include "SkCanvas.h"
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkSurface_Base::SkSurface_Base(int width, int height) : INHERITED(width, height) {
     fCachedCanvas = NULL;
     fCachedImage = NULL;
 }
 
+SkSurface_Base::SkSurface_Base(const SkImageInfo& info) : INHERITED(info) {
+    fCachedCanvas = NULL;
+    fCachedImage = NULL;
+}
+
 SkSurface_Base::~SkSurface_Base() {
     // in case the canvas outsurvives us, we null the callback
     if (fCachedCanvas) {
         fCachedCanvas->setSurfaceBase(NULL);
     }
 
     SkSafeUnref(fCachedImage);
     SkSafeUnref(fCachedCanvas);
 }
 
@@ skipping 37 matching lines @@
     return sk_atomic_inc(&gID) + 1;
 }
 
 static SkSurface_Base* asSB(SkSurface* surface) {
     return static_cast<SkSurface_Base*>(surface);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkSurface::SkSurface(int width, int height) : fWidth(width), fHeight(height) {
-    SkASSERT(width >= 0);
-    SkASSERT(height >= 0);
+    SkASSERT(fWidth >= 0);
+    SkASSERT(fHeight >= 0);
     fGenerationID = 0;
 }
 
+SkSurface::SkSurface(const SkImageInfo& info)
+    : fWidth(info.fWidth)
+    , fHeight(info.fHeight)
+{
+    SkASSERT(fWidth >= 0);
+    SkASSERT(fHeight >= 0);
+    fGenerationID = 0;
+}
+
 uint32_t SkSurface::generationID() {
     if (0 == fGenerationID) {
         fGenerationID = asSB(this)->newGenerationID();
     }
     return fGenerationID;
 }
 
 void SkSurface::notifyContentWillChange(ContentChangeMode mode) {
     asSB(this)->aboutToDraw(mode);
 }
 
 SkCanvas* SkSurface::getCanvas() {
     return asSB(this)->getCachedCanvas();
 }
 
 SkImage* SkSurface::newImageSnapshot() {
     SkImage* image = asSB(this)->getCachedImage();
     SkSafeRef(image);   // the caller will call unref() to balance this
     return image;
 }
 
 SkSurface* SkSurface::newSurface(const SkImageInfo& info) {
     return asSB(this)->onNewSurface(info);
 }
 
 void SkSurface::draw(SkCanvas* canvas, SkScalar x, SkScalar y,
                      const SkPaint* paint) {
     return asSB(this)->onDraw(canvas, x, y, paint);
 }