Implement SkPicture::bytesUsed() for SkRecord backend

src/utils/SkPictureUtils.cpp

Index: src/utils/SkPictureUtils.cpp
diff --git a/src/utils/SkPictureUtils.cpp b/src/utils/SkPictureUtils.cpp
index dfa772a2da5be93e24bc645608c41052218f6822..73c61bb042871ca21907d396a8ffd9b48a5518cb 100644
--- a/src/utils/SkPictureUtils.cpp
+++ b/src/utils/SkPictureUtils.cpp
@@ -5,6 +5,7 @@
  * found in the LICENSE file.
  */
 
+#include "SkBBoxHierarchy.h"
 #include "SkBitmapDevice.h"
 #include "SkCanvas.h"
 #include "SkData.h"
@@ -12,6 +13,7 @@
 #include "SkPictureUtils.h"
 #include "SkPixelRef.h"
 #include "SkRRect.h"
+#include "SkRecord.h"
 #include "SkShader.h"
 
 class PixelRefSet {
@@ -215,3 +217,29 @@ SkData* SkPictureUtils::GatherPixelRefs(const SkPicture* pict, const SkRect& are
     }
     return data;
 }
+
+struct MeasureRecords {
+    template <typename T> size_t operator()(const T& op) { return 0; }
+    size_t operator()(const SkRecords::DrawPicture& op) {
+        return SkPictureUtils::ApproximateBytesUsed(op.picture);
+    }
+};
+
+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->fDeletionListeners.reserved() * sizeof(SkPicture::DeletionListener*) +
+        pict->fDeletionListeners.count() * sizeof(SkPicture::DeletionListener);
+
+    MeasureRecords visitor;
+    for (unsigned curOp = 0; curOp < pict->fRecord->count(); curOp++) {
+        byteCount += pict->fRecord->visit<size_t>(curOp, visitor);
+    }
+
+    return byteCount;
+}