Add drawRegion() API to SkCanvas

include/core/SkCanvas.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkCanvas_DEFINED
 #define SkCanvas_DEFINED
 
@@ skipping 684 matching lines @@
         will be filled or framed based on the Style in the paint.
         @param left     The left side of the rectangle to be drawn
         @param top      The top side of the rectangle to be drawn
         @param right    The right side of the rectangle to be drawn
         @param bottom   The bottom side of the rectangle to be drawn
         @param paint    The paint used to draw the rect
     */
     void drawRectCoords(SkScalar left, SkScalar top, SkScalar right,
                         SkScalar bottom, const SkPaint& paint);
 
+    /** Draw the outline of the specified region using the specified paint.
+        @param region   The region to be drawn
+        @param paint    The paint used to draw the region
+    */
+    void drawRegion(const SkRegion& region, const SkPaint& paint) {

[reed1, 2016/08/26 12:27:02]

tiny nit: most of these non-virtuals we also put in the cpp. We should think
about detecting empty and just-a-rect at this level, before we dispatch to the
virtuals.

[msarett, 2016/08/26 13:20:14]

SGTM, see https://codereview.chromium.org/2286693002/

+        this->onDrawRegion(region, paint);
+    }
+
     /** Draw the specified oval using the specified paint. The oval will be
         filled or framed based on the Style in the paint.
         @param oval     The rectangle bounds of the oval to be drawn
         @param paint    The paint used to draw the oval
     */
     void drawOval(const SkRect& oval, const SkPaint&);
 
     /**
      *  Draw the specified RRect using the specified paint The rrect will be filled or stroked
      *  based on the Style in the paint.
@@ skipping 667 matching lines @@
     virtual void onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
                                 const SkPaint& paint);
 
     virtual void onDrawPatch(const SkPoint cubics[12], const SkColor colors[4],
                            const SkPoint texCoords[4], SkXfermode* xmode, const SkPaint& paint);
 
     virtual void onDrawDrawable(SkDrawable*, const SkMatrix*);
 
     virtual void onDrawPaint(const SkPaint&);
     virtual void onDrawRect(const SkRect&, const SkPaint&);
+    virtual void onDrawRegion(const SkRegion& region, const SkPaint& paint);
     virtual void onDrawOval(const SkRect&, const SkPaint&);
     virtual void onDrawArc(const SkRect&, SkScalar startAngle, SkScalar sweepAngle, bool useCenter,
                            const SkPaint&);
     virtual void onDrawRRect(const SkRRect&, const SkPaint&);
     virtual void onDrawPoints(PointMode, size_t count, const SkPoint pts[], const SkPaint&);
     virtual void onDrawVertices(VertexMode, int vertexCount, const SkPoint vertices[],
                                 const SkPoint texs[], const SkColor colors[], SkXfermode*,
                                 const uint16_t indices[], int indexCount, const SkPaint&);
 
     virtual void onDrawAtlas(const SkImage*, const SkRSXform[], const SkRect[], const SkColor[],
@@ skipping 284 matching lines @@
 
 class SkCanvasClipVisitor {
 public:
     virtual ~SkCanvasClipVisitor();
     virtual void clipRect(const SkRect&, SkRegion::Op, bool antialias) = 0;
     virtual void clipRRect(const SkRRect&, SkRegion::Op, bool antialias) = 0;
     virtual void clipPath(const SkPath&, SkRegion::Op, bool antialias) = 0;
 };
 
 #endif