change drawPicture in SkRecord to just ref the picture

src/core/SkRecord.h

Index: src/core/SkRecord.h
diff --git a/src/core/SkRecord.h b/src/core/SkRecord.h
index 6c5177eefb6c4464b27c111c42dd4b605a40442d..96da69b12ef8c150729c07c8e846fab5452cb1dc 100644
--- a/src/core/SkRecord.h
+++ b/src/core/SkRecord.h
@@ -64,7 +64,7 @@ public:
     // Allocate contiguous space for count Ts, to be freed when the SkRecord is destroyed.
     // Here T can be any class, not just those from SkRecords.  Throws on failure.
     template <typename T>
-    T* alloc(unsigned count = 1) {
+    T* alloc(size_t count = 1) {
         return (T*)fAlloc.allocThrow(sizeof(T) * count);
     }