add SkDrawPictureCallback optional parameter to drawPicture(), which can abort the picture drawing.

src/core/SkCanvas.cpp

 
 /*
  * Copyright 2008 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.
  */
 
 
 #include "SkCanvas.h"
@@ skipping 2113 matching lines @@
                                 const SkPath& path, SkScalar hOffset,
                                 SkScalar vOffset, const SkPaint& paint) {
     SkMatrix    matrix;
 
     matrix.setTranslate(hOffset, vOffset);
     this->drawTextOnPath(text, byteLength, path, &matrix, paint);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
-void SkCanvas::drawPicture(SkPicture& picture) {
-    picture.draw(this);
+void SkCanvas::drawPicture(SkPicture& pict, SkDrawPictureCallback* callback) {
+    pict.draw(this, callback);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////
 
 SkCanvas::LayerIter::LayerIter(SkCanvas* canvas, bool skipEmptyClips) {
     SK_COMPILE_ASSERT(sizeof(fStorage) >= sizeof(SkDrawIter), fStorage_too_small);
 
     SkASSERT(canvas);
 
@@ skipping 25 matching lines @@
     return *paint;
 }
 
 const SkRegion& SkCanvas::LayerIter::clip() const { return fImpl->getClip(); }
 int SkCanvas::LayerIter::x() const { return fImpl->getX(); }
 int SkCanvas::LayerIter::y() const { return fImpl->getY(); }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkCanvas::ClipVisitor::~ClipVisitor() { }