Only count uniquely named native scripts for debug.

test/mjsunit/debug-script.js

Index: test/mjsunit/debug-script.js
diff --git a/test/mjsunit/debug-script.js b/test/mjsunit/debug-script.js
index 643dd8ce42f0bd5403713147c810e59b1e7444d5..9767888f7cfc4caaf245b954c8bd1b1d319c4a9a 100644
--- a/test/mjsunit/debug-script.js
+++ b/test/mjsunit/debug-script.js
@@ -34,13 +34,19 @@ 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++;