Revert of Sketch splitting SkPicture into an interface and SkBigPicture.

include/utils/SkPictureUtils.h

Index: include/utils/SkPictureUtils.h
diff --git a/include/utils/SkPictureUtils.h b/include/utils/SkPictureUtils.h
index b65a64d57924fa39f7e4b5472e86883fdcb77036..10607da9c67b048e78801b879fb13744fa7305e0 100644
--- a/include/utils/SkPictureUtils.h
+++ b/include/utils/SkPictureUtils.h
@@ -10,8 +10,6 @@
 
 #include "SkPicture.h"
 
-// TODO: remove this file?
-
 class SK_API SkPictureUtils {
 public:
     /**
@@ -20,9 +18,7 @@
      *  includes nested SkPictures, but does not include large objects that
      *  SkRecord holds a reference to (e.g. paths, or pixels backing bitmaps).
      */
-    static size_t ApproximateBytesUsed(const SkPicture* pict) {
-        return pict->approximateBytesUsed();
-    }
+    static size_t ApproximateBytesUsed(const SkPicture* pict);
 };
 
 #endif