create cairo before we hand-off the surface, in case the surface is destroyed

skia/ext/bitmap_platform_device_cairo.h

 // Copyright 2013 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_EXT_BITMAP_PLATFORM_DEVICE_CAIRO_H_
 #define SKIA_EXT_BITMAP_PLATFORM_DEVICE_CAIRO_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
@@ skipping 45 matching lines @@
 // shared memory between the renderer and the main process at least. In this
 // case we'll probably create the buffer from a precreated region of memory.
 // -----------------------------------------------------------------------------
 class BitmapPlatformDevice : public SkBitmapDevice, public PlatformDevice {
  public:
   // Create a BitmapPlatformDeviceLinux from an already constructed bitmap;
   // you should probably be using Create(). This may become private later if
   // we ever have to share state between some native drawing UI and Skia, like
   // the Windows and Mac versions of this class do.
   //
-  // This object takes ownership of @data.
-  BitmapPlatformDevice(const SkBitmap& other, cairo_surface_t* surface);
+  // This object takes ownership of @cairo.
+  BitmapPlatformDevice(const SkBitmap& other, cairo_t* cairo);
   virtual ~BitmapPlatformDevice();
 
   // Constructs a device with size |width| * |height| with contents initialized
   // to zero. |is_opaque| should be set if the caller knows the bitmap will be
   // completely opaque and allows some optimizations.
   static BitmapPlatformDevice* Create(int width, int height, bool is_opaque);
 
   // Performs the same construction as Create.
   // Other ports require a separate construction routine because Create does not
   // initialize the bitmap to 0.
@@ skipping 46 matching lines @@
 
   // The current clipping
   SkRegion clip_region_;
 
   DISALLOW_COPY_AND_ASSIGN(BitmapPlatformDevice);
 };
 
 }  // namespace skia
 
 #endif  // SKIA_EXT_BITMAP_PLATFORM_DEVICE_CAIRO_H_