Fix false x64 argument index assertion

test/mjsunit/regress/regress-355486.js

Index: test/mjsunit/regress/regress-355486.js
diff --git a/test/mjsunit/regress/regress-347542.js b/test/mjsunit/regress/regress-355486.js
similarity index 64%
copy from test/mjsunit/regress/regress-347542.js
copy to test/mjsunit/regress/regress-355486.js
index 901d798fb7fbea45f0d9f3d8ba6c7a9846bf6dd6..55362a13416335b72bfa1ff92bc29f7a04edbd65 100644
--- a/test/mjsunit/regress/regress-347542.js
+++ b/test/mjsunit/regress/regress-355486.js
@@ -4,8 +4,10 @@
 
 // Flags: --allow-natives-syntax
 
-function foo() {}
-foo();
-%OptimizeFunctionOnNextCall(foo);
-foo();
-%NeverOptimizeFunction(foo);
+function f() { var v = arguments[0]; }
+function g() { f(); }
+
+g();
+g();
+%OptimizeFunctionOnNextCall(g);
+g();