Add PlatformPictureSkia and RecordingPlatformDeviceSkia.

skia/ext/platform_canvas.h

Index: skia/ext/platform_canvas.h
diff --git a/skia/ext/platform_canvas.h b/skia/ext/platform_canvas.h
index cbeb95b2bbe252cf5c5ebc7bd3abeeb3ad29dcf8..5424da4186a278319fa24d1790f43287834842ab 100644
--- a/skia/ext/platform_canvas.h
+++ b/skia/ext/platform_canvas.h
@@ -120,6 +120,10 @@ SK_API SkCanvas* TryCreateBitmapCanvas(int width, int height, bool is_opaque);
 // return NULL PlatformSurface.
 SK_API bool SupportsPlatformPaint(const SkCanvas* canvas);
 
+// Returns true if native platform routines can be used to draw on the
+// given canvas without any indirect rendering taking place.

[alokp, 2012/09/17 16:29:30]

I am not quite clear on the differences between these two functions. May be a
comment about usage would help.

[reed1, 2012/09/17 16:51:24]

+1 -- not sure the diff between these two functions.

[reveman, 2012/09/17 21:22:16]

Sure, does updating the comment to the following make it clear?

// Returns true if native platform routines can be used to draw on the          
// given canvas without any indirect rendering taking place. Indirect           
// rendering can be expensive so it's recommended to avoid using                
// platform paint if possible when direct platform paint isn't supported.       
// E.g. if there's a method to perform text rendering without platform          
// paint then it's likely much more efficient to use that method in the         
// case where this function returns false.

[nduca, 2012/09/18 09:54:24]

Done.

[nduca, 2012/09/18 09:54:24]

Would a better tweak for this be to change SupportsPlatformPaint to be more like
a capabilities query that returns an enum? PlatformPaintIndirect  |
PlatformPaintDirect | Unsupported?

[reveman, 2012/09/18 17:56:15]

I left this as SupportsPlatformPaint/SupportsDirectPlatformPaint in the latest
patch but I'd be fine changing this to:

enum PlatformPaintType {
  PlatformPaintUnsupported = 0,
  PlatformPaintIndirect,
  PlatformPaintDirect
};
PlatformPaintType PlatformPaintSupport();

if that would be preferred?

+SK_API bool SupportsDirectPlatformPaint(const SkCanvas* canvas);
+
 // Draws into the a native platform surface, |context|.  Forwards to
 // DrawToNativeContext on a PlatformDevice instance bound to the top device.
 // If no PlatformDevice instance is bound, is a no-operation.