HeapProfiler: provide human readable names for code objects.

src/builtins.h

Index: src/builtins.h
diff --git a/src/builtins.h b/src/builtins.h
index 9b589d843de90960bb5fa432c50a8c80337c6237..2df4b186dbc90ae1dc7e2062c6046dc6d17a39e5 100644
--- a/src/builtins.h
+++ b/src/builtins.h
@@ -364,6 +364,11 @@ class Builtins {
   }
 
   static const char* GetName(JavaScript id) { return javascript_names_[id]; }
+  const char* name(int index) {
+    ASSERT(index >= 0);
+    ASSERT(index < id_count);
+    return names_[index];
+  }
   static int GetArgumentsCount(JavaScript id) { return javascript_argc_[id]; }
   Handle<Code> GetCode(JavaScript id, bool* resolved);
   static int NumberOfJavaScriptBuiltins() { return id_count; }