add endRecordingAsDrawable experiment

src/core/SkPicture.cpp

Index: src/core/SkPicture.cpp
diff --git a/src/core/SkPicture.cpp b/src/core/SkPicture.cpp
index b24f7196d0d25f13b55149c94fb6bf764f70e353..acc7af4329902ac4aee4f03b01faea43785388fd 100644
--- a/src/core/SkPicture.cpp
+++ b/src/core/SkPicture.cpp
@@ -279,6 +279,7 @@ SkPicture const* const* SkPicture::drawablePicts() const {
 
 SkPicture::~SkPicture() {
     this->callDeletionListeners();
+    fRecord.reset(NULL);
 }
 
 void SkPicture::EXPERIMENTAL_addAccelData(const SkPicture::AccelData* data) const {
@@ -521,9 +522,9 @@ SkPicture::SkPicture(const SkRect& cullRect, SkRecord* record, SnapshotArray* dr
                      SkBBoxHierarchy* bbh)
     : fUniqueID(next_picture_generation_id())
     , fCullRect(cullRect)
-    , fRecord(record)
+    , fRecord(SkRef(record))
     , fBBH(SkSafeRef(bbh))
-    , fDrawablePicts(drawablePicts)
+    , fDrawablePicts(drawablePicts)     // take ownership
     , fAnalysis(*fRecord)
 {}