Refactor the PlatformContext layer to have only one class.

skia/ext/bitmap_platform_device_win.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SKIA_BITMAP_PLATFORM_DEVICE_WIN_H_
 #define SKIA_BITMAP_PLATFORM_DEVICE_WIN_H_
 
 #include "skia/ext/platform_device_win.h"
 
 namespace skia {
 
 // A device is basically a wrapper around SkBitmap that provides a surface for
 // SkCanvas to draw into. Our device provides a surface Windows can also write
-// to. BitmapPlatformDeviceWin creates a bitmap using CreateDIBSection() in a
+// to. BitmapPlatformDevice creates a bitmap using CreateDIBSection() in a
 // format that Skia supports and can then use this to draw ClearType into, etc.
 // This pixel data is provided to the bitmap that the device contains so that it
 // can be shared.
 //
 // The device owns the pixel data, when the device goes away, the pixel data
 // also becomes invalid. THIS IS DIFFERENT THAN NORMAL SKIA which uses
 // reference counting for the pixel data. In normal Skia, you could assign
 // another bitmap to this device's bitmap and everything will work properly.
 // For us, that other bitmap will become invalid as soon as the device becomes
 // invalid, which may lead to subtle bugs. Therefore, DO NOT ASSIGN THE
 // DEVICE'S PIXEL DATA TO ANOTHER BITMAP, make sure you copy instead.
-class BitmapPlatformDeviceWin : public PlatformDeviceWin {
+class BitmapPlatformDevice : public PlatformDevice {
  public:
   // Factory function. The screen DC is used to create the bitmap, and will not
   // be stored beyond this function. is_opaque should be set if the caller
   // knows the bitmap will be completely opaque and allows some optimizations.
   //
   // The shared_section parameter is optional (pass NULL for default behavior).
   // If shared_section is non-null, then it must be a handle to a file-mapping
   // object returned by CreateFileMapping.  See CreateDIBSection for details.
-  static BitmapPlatformDeviceWin* create(HDC screen_dc,
-                                         int width,
-                                         int height,
-                                         bool is_opaque,
-                                         HANDLE shared_section);
+  static BitmapPlatformDevice* create(HDC screen_dc,
+                                      int width,
+                                      int height,
+                                      bool is_opaque,
+                                      HANDLE shared_section);
+
+  // This version is the same as above but will get the screen DC itself.
+  static BitmapPlatformDevice* create(int width,
+                                      int height,
+                                      bool is_opaque,
+                                      HANDLE shared_section);
 
   // Copy constructor. When copied, devices duplicate their internal data, so
   // stay linked. This is because their implementation is very heavyweight
   // (lots of memory and some GDI objects). If a device has been copied, both
   // clip rects and other state will stay in sync.
   //
   // This means it will NOT work to duplicate a device and assign it to a
   // canvas, because the two canvases will each set their own clip rects, and
   // the resulting GDI clip rect will be random.
   //
   // Copy constucting and "=" is designed for saving the device or passing it
   // around to another routine willing to deal with the bitmap data directly.
-  BitmapPlatformDeviceWin(const BitmapPlatformDeviceWin& other);
-  virtual ~BitmapPlatformDeviceWin();
+  BitmapPlatformDevice(const BitmapPlatformDevice& other);
+  virtual ~BitmapPlatformDevice();
 
   // See warning for copy constructor above.
-  BitmapPlatformDeviceWin& operator=(const BitmapPlatformDeviceWin& other);
+  BitmapPlatformDevice& operator=(const BitmapPlatformDevice& other);
 
   // Retrieves the bitmap DC, which is the memory DC for our bitmap data. The
   // bitmap DC is lazy created.
   virtual HDC getBitmapDC();
   virtual void setMatrixClip(const SkMatrix& transform, const SkRegion& region);
 
   virtual void drawToHDC(HDC dc, int x, int y, const RECT* src_rect);
   virtual void makeOpaque(int x, int y, int width, int height);
   virtual bool IsVectorial() { return false; }
 
   // Returns the color value at the specified location. This does not
   // consider any transforms that may be set on the device.
   SkColor getColorAt(int x, int y);
 
  protected:
   // Flushes the Windows device context so that the pixel data can be accessed
   // directly by Skia. Overridden from SkDevice, this is called when Skia
   // starts accessing pixel data.
   virtual void onAccessBitmap(SkBitmap* bitmap);
 
  private:
   // Reference counted data that can be shared between multiple devices. This
   // allows copy constructors and operator= for devices to work properly. The
   // bitmaps used by the base device class are already refcounted and copyable.
-  class BitmapPlatformDeviceWinData;
+  class BitmapPlatformDeviceData;
 
   // Private constructor. The data should already be ref'ed for us.
-  BitmapPlatformDeviceWin(BitmapPlatformDeviceWinData* data,
-                          const SkBitmap& bitmap);
+  BitmapPlatformDevice(BitmapPlatformDeviceData* data,
+                       const SkBitmap& bitmap);
 
   // Data associated with this device, guaranteed non-null. We hold a reference
   // to this object.
-  BitmapPlatformDeviceWinData* data_;
+  BitmapPlatformDeviceData* data_;
 };
 
 }  // namespace skia
 
 #endif  // SKIA_BITMAP_PLATFORM_DEVICE_WIN_H_