Revert of Sketch splitting SkPicture into an interface and SkBigPicture.

src/utils/SkPictureUtils.cpp

+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkBBoxHierarchy.h"
+#include "SkCanvas.h"
+#include "SkData.h"
+#include "SkPictureUtils.h"
+#include "SkRecord.h"
+#include "SkShader.h"
+
+size_t SkPictureUtils::ApproximateBytesUsed(const SkPicture* pict) {
+    size_t byteCount = sizeof(*pict);
+
+    byteCount += pict->fRecord->bytesUsed();
+    if (pict->fBBH.get()) {
+        byteCount += pict->fBBH->bytesUsed();
+    }
+    byteCount += pict->fApproxBytesUsedBySubPictures;
+
+    return byteCount;
+}