[SkDebugger] Flatten drawPicture ops

src/utils/debugger/SkDebugCanvas.cpp

Index: src/utils/debugger/SkDebugCanvas.cpp
diff --git a/src/utils/debugger/SkDebugCanvas.cpp b/src/utils/debugger/SkDebugCanvas.cpp
index b1e906ae9044f7fc362181ba33eb5676434bcb03..1b50efaa325b7b6f677b869cfa4b1c3926aa0bf9 100644
--- a/src/utils/debugger/SkDebugCanvas.cpp
+++ b/src/utils/debugger/SkDebugCanvas.cpp
@@ -459,7 +459,9 @@ void SkDebugCanvas::onDrawPath(const SkPath& path, const SkPaint& paint) {
 void SkDebugCanvas::onDrawPicture(const SkPicture* picture,
                                   const SkMatrix* matrix,
                                   const SkPaint* paint) {
-    this->addDrawCommand(new SkDrawPictureCommand(picture, matrix, paint));
+    this->addDrawCommand(new SkBeginDrawPictureCommand(picture, matrix, paint));
+    this->INHERITED::onDrawPicture(picture, matrix, paint);
+    this->addDrawCommand(new SkEndDrawPictureCommand(SkToBool(matrix) || SkToBool(paint)));
 }
 
 void SkDebugCanvas::onDrawPoints(PointMode mode, size_t count,