Fix bug restoring of JS entry sp so to fix profiler-related valgrind issues.

src/frames.h

Index: src/frames.h
===================================================================
--- src/frames.h	(revision 7902)
+++ src/frames.h	(working copy)
@@ -152,6 +152,12 @@
     NO_ID = 0
   };
 
+  // Used to mark the outermost JS entry frame.
+  enum JsFrameMarker {
+    INNER_JSENTRY_FRAME = 0,
+    OUTERMOST_JSENTRY_FRAME = 1
+  };
+
   struct State {
     State() : sp(NULL), fp(NULL), pc_address(NULL) { }
     Address sp;