Record SkCanvas::flush().

We can record multiple frames in an .skp by recording SkCanvas::flush().
This should make SkPictures, SkLiteDL, and .skp files all record flush().

Change-Id: I6cf6e0e4ef993530d9f92fa168a53702ffce7d5e
Reviewed-on: https://skia-review.googlesource.com/34081
Reviewed-by: Derek Sollenberger <djsollen@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
diff --git a/src/core/SkPictureRecord.h b/src/core/SkPictureRecord.h
index 9a93bf9..f3d991a 100644
--- a/src/core/SkPictureRecord.h
+++ b/src/core/SkPictureRecord.h
@@ -157,6 +157,8 @@
     sk_sp<SkSurface> onNewSurface(const SkImageInfo&, const SkSurfaceProps&) override;
     bool onPeekPixels(SkPixmap*) override { return false; }
 
+    void onFlush() override;
+
     void willSave() override;
     SaveLayerStrategy getSaveLayerStrategy(const SaveLayerRec&) override;
     void willRestore() override;