add SkPictureUtils::GatherPixelRefs()
Review URL: https://codereview.appspot.com/6845106

git-svn-id: http://skia.googlecode.com/svn/trunk@6615 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tools/PictureRenderer.h b/tools/PictureRenderer.h
index 8d9a6bd..8bce978 100644
--- a/tools/PictureRenderer.h
+++ b/tools/PictureRenderer.h
@@ -367,6 +367,8 @@
     typedef PictureRenderer INHERITED;
 };
 
+extern PictureRenderer* CreateGatherPixelRefsRenderer();
+
 }
 
 #endif  // PictureRenderer_DEFINED