Make optimized Function.prototype.apply safe for non-JSObject first arguments.

test/mjsunit/compiler/regress-arguments.js

Index: test/mjsunit/compiler/regress-arguments.js
diff --git a/test/mjsunit/compiler/regress-arguments.js b/test/mjsunit/compiler/regress-arguments.js
index 234d3fbc974dafd36a3fb915e58648fd55641434..ebae5a03998b2cb5dd63d7d0b519b93635d359cd 100644
--- a/test/mjsunit/compiler/regress-arguments.js
+++ b/test/mjsunit/compiler/regress-arguments.js
@@ -46,4 +46,7 @@ function u() {
  return f.apply(v, arguments);
 }
 
-for (var i=0; i<1000000; i++) assertEquals(void 0, u());
+Number.prototype.foo = 42;
+delete Number.prototype.foo;
+
+for (var i=0; i<100000; i++) assertEquals(void 0, u());