Fix -ftime-report for C++ lookup.

Found this while running -ftime-report on a largish C++ source file.
We need to start TV_NAME_LOOKUP conditionally inside poplevel()
because it may be called from another lookup routine that already has
TV_NAME_LOOKUP going.

Tested on x86_64.  Committed to trunk.

2012-08-20  Diego Novillo  <dnovillo@google.com>

	* decl.c (poplevel): Start TV_NAME_LOOKUP conditionally.

From-SVN: r190535

gcc/cp/ChangeLog

+2012-08-20  Diego Novillo  <dnovillo@google.com>
+
+	* decl.c (poplevel): Start TV_NAME_LOOKUP conditionally.
+
 2012-08-20  Richard Guenther  <rguenther@suse.de>
 
 	* name-lookup.c (store_binding_p): New predicate, split out from ...

gcc/cp/decl.c

@@ -552,7 +552,7 @@ poplevel (int keep, int reverse, int functionbody)
   unsigned ix;
   cp_label_binding *label_bind;
 
-  timevar_start (TV_NAME_LOOKUP);
+  bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
  restart:
 
   block = NULL_TREE;
@@ -818,7 +818,7 @@ poplevel (int keep, int reverse, int functionbody)
   if (kind == sk_cleanup)
     goto restart;
 
-  timevar_stop (TV_NAME_LOOKUP);
+  timevar_cond_stop (TV_NAME_LOOKUP, subtime);
   return block;
 }