Modify skia serve to return clip rect and view matrix

tools/json/SkJSONCanvas.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkJSONCanvas_DEFINED
 #define SkJSONCanvas_DEFINED
 
@@ skipping 131 matching lines @@
  * SkJSONRenderer. Be sure to call finish() when you are done drawing.
  */
 class SkJSONCanvas : public SkCanvas {
 public:
     /* Create a canvas which writes to the specified output stream. */
     SkJSONCanvas(int width, int height, SkWStream& out, bool sendBinaries = false);
 
     /* Complete the JSON document. */
     void finish();
 
+    static Json::Value MakeMatrix(const SkMatrix& matrix);
+
+    static Json::Value MakeIRect(const SkIRect& irect);
+
     // overridden SkCanvas API
 
     void onDrawPaint(const SkPaint&) override;
 
     void onDrawRect(const SkRect&, const SkPaint&) override;
 
     void onDrawOval(const SkRect&, const SkPaint&) override;
 
     void onDrawRRect(const SkRRect&, const SkPaint&) override;
 
@@ skipping 57 matching lines @@
 
     void onClipRegion(const SkRegion& deviceRgn, SkRegion::Op op) override;
 
     void willSave() override;
 
     void willRestore() override;
 
     SkCanvas::SaveLayerStrategy getSaveLayerStrategy(const SaveLayerRec& rec) override;
 
 private:
+    // Helpers to turn values into JSON, these could probably be static
     Json::Value makePoint(const SkPoint& point);
 
     Json::Value makePoint(SkScalar x, SkScalar y);
 
     Json::Value makeRect(const SkRect& rect);
 
     Json::Value makeRRect(const SkRRect& rrect);
 
     Json::Value makePath(const SkPath& path);
 
     Json::Value makeRegion(const SkRegion& region);
   
     Json::Value makePaint(const SkPaint& paint);
   
     Json::Value makeRegionOp(SkRegion::Op op);
   
     Json::Value makeEdgeStyle(SkCanvas::ClipEdgeStyle edgeStyle);
   
     Json::Value makePointMode(SkCanvas::PointMode mode);
-  
-    Json::Value makeMatrix(const SkMatrix& matrix);
-  
+
     void updateMatrix();
 
     SkWStream&  fOut;
     SkMatrix    fLastMatrix;
     Json::Value fRoot;
     Json::Value fCommands;
     bool        fSendBinaries;
 
     typedef SkCanvas INHERITED;
 };
 
 #endif