Debugger: use debug break slots to break at function exit.

src/objects-debug.cc

Index: src/objects-debug.cc
diff --git a/src/objects-debug.cc b/src/objects-debug.cc
index a3d96b9d034228462a36c559c43a4bcdc21645ba..4587d2e596b680edf08dd25ec7ae770ad82c2919 100644
--- a/src/objects-debug.cc
+++ b/src/objects-debug.cc
@@ -1029,7 +1029,6 @@ void NormalizedMapCache::NormalizedMapCacheVerify() {
 void DebugInfo::DebugInfoVerify() {
   CHECK(IsDebugInfo());
   VerifyPointer(shared());
-  VerifyPointer(original_code());
   VerifyPointer(code());
   VerifyPointer(break_points());
 }