Add allocation sites to scratchpad only if a significant amount of mementos was found.

BUG=
R=titzer@chromium.org

Review URL: https://codereview.chromium.org/284223007

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21370 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/objects-inl.h

@@ -1566,7 +1566,7 @@ inline bool AllocationSite::IncrementMementoFoundCount() {
 
   int value = memento_found_count();
   set_memento_found_count(value + 1);
-  return value == 0;
+  return value == kPretenureMinimumCreated;
 }