Factor code to rotate a canvas about a point.

samplecode/SampleCircle.cpp

Index: samplecode/SampleCircle.cpp
diff --git a/samplecode/SampleCircle.cpp b/samplecode/SampleCircle.cpp
index ff88ac4b9b7c7c96aacb4d3f4a09298a27043400..f4e6cc99b480865d69b5436a9e17a3781f8bf452 100644
--- a/samplecode/SampleCircle.cpp
+++ b/samplecode/SampleCircle.cpp
@@ -87,17 +87,10 @@ protected:
         path->close();
     }
 
-    static void rotate(SkCanvas* canvas, SkScalar angle, SkScalar px, SkScalar py) {
-        canvas->translate(-px, -py);
-        canvas->rotate(angle);
-        canvas->translate(px, py);
-    }
-
     virtual void onDrawContent(SkCanvas* canvas) {
         SkPaint paint;
         paint.setAntiAlias(true);
         paint.setStyle(SkPaint::kStroke_Style);
-//        canvas->drawCircle(250, 250, 220, paint);
         SkMatrix matrix;
         matrix.setScale(SkIntToScalar(100), SkIntToScalar(100));
         matrix.postTranslate(SkIntToScalar(200), SkIntToScalar(200));