Only count uniquely named native scripts for debug.

test/mjsunit/debug-script.js

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 16 matching lines @@
 
 // Flags: --expose-debug-as debug --expose-gc
 // Get the Debug object exposed from the debug context global object.
 Debug = debug.Debug
 
 Date();
 RegExp();
 
 // Count script types.
 var named_native_count = 0;
+var named_native_names = {};
 var extension_count = 0;
 var normal_count = 0;
 var scripts = Debug.scripts();
 for (i = 0; i < scripts.length; i++) {
   if (scripts[i].type == Debug.ScriptType.Native) {
     if (scripts[i].name) {
-      named_native_count++;
+      // TODO(1641): Remove check for equally named native scripts once the
+      // underlying issue is fixed.
+      if (!named_native_names[scripts[i].name]) {
+        named_native_names[scripts[i].name] = true;
+        named_native_count++;
+      }
     }
   } else if (scripts[i].type == Debug.ScriptType.Extension) {
     extension_count++;
   } else if (scripts[i].type == Debug.ScriptType.Normal) {
     normal_count++;
   } else {
     assertUnreachable('Unexpected type ' + scripts[i].type);
   }
 }
 
@@ skipping 29 matching lines @@
 }
 
 // Test a normal script.
 var mjsunit_js_script = Debug.findScript(/mjsunit.js/);
 assertTrue(/mjsunit.js/.test(mjsunit_js_script.name));
 assertEquals(Debug.ScriptType.Normal, mjsunit_js_script.type);
 
 // Check a nonexistent script.
 var dummy_script = Debug.findScript('dummy.js');
 assertTrue(typeof dummy_script == 'undefined');