Implement drawDRRect for GPU

include/gpu/GrContext.h

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrContext_DEFINED
 #define GrContext_DEFINED
 
@@ skipping 439 matching lines @@
                         const SkMatrix* dstMatrix = NULL,
                         const SkMatrix* localMatrix = NULL);
 
     /**
      *  Draw a roundrect using a paint.
      *
      *  @param paint        describes how to color pixels.
      *  @param rrect        the roundrect to draw
      *  @param stroke       the stroke information (width, join, cap)
      */
-    void drawRRect(const GrPaint& paint,
-                   const SkRRect& rrect,
-                   const SkStrokeRec& stroke);
+    void drawRRect(const GrPaint& paint, const SkRRect& rrect, const SkStrokeRec& stroke);
+
+    /**
+     *  Shortcut for drawing an SkPath consisting of nested rrects using a paint.
+     *  Does not support stroking. The result is undefined if outer does not contain
+     *  inner.
+     *
+     *  @param paint        describes how to color pixels.
+     *  @param outer        the outer roundrect
+     *  @param inner        the inner roundrect
+     */
+    void drawDRRect(const GrPaint& paint, const SkRRect& outer, const SkRRect& inner);
+
 
     /**
      * Draws a path.
      *
      * @param paint         describes how to color pixels.
      * @param path          the path to draw
      * @param stroke        the stroke information (width, join, cap)
      */
     void drawPath(const GrPaint& paint, const SkPath& path, const SkStrokeRec& stroke);
 
@@ skipping 605 matching lines @@
     }
 
     GrTexture* texture() { return fTexture; }
 
 private:
     GrContext*                    fContext;
     GrTexture*                    fTexture;
 };
 
 #endif