Cleanup of mjsunit.js code and make assertEquals more strict.

test/mjsunit/regress/regress-1199637.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: --allow-natives-syntax
 
 // Make sure that we can introduce global variables (using
 // both var and const) that shadow even READ_ONLY variables
 // in the prototype chain.
 const NONE = 0;
 const READ_ONLY = 1;
 
 // Use DeclareGlobal...
-%SetProperty(this.__proto__, "a", "1234", NONE);
+%SetProperty(this.__proto__, "a", 1234, NONE);
 assertEquals(1234, a);
 eval("var a = 5678;");
 assertEquals(5678, a);
 
-%SetProperty(this.__proto__, "b", "1234", NONE);
+%SetProperty(this.__proto__, "b", 1234, NONE);
 assertEquals(1234, b);
 eval("const b = 5678;");
 assertEquals(5678, b);
 
-%SetProperty(this.__proto__, "c", "1234", READ_ONLY);
+%SetProperty(this.__proto__, "c", 1234, READ_ONLY);
 assertEquals(1234, c);
 eval("var c = 5678;");
 assertEquals(5678, c);
 
-%SetProperty(this.__proto__, "d", "1234", READ_ONLY);
+%SetProperty(this.__proto__, "d", 1234, READ_ONLY);
 assertEquals(1234, d);
 eval("const d = 5678;");
 assertEquals(5678, d);
 
 // Use DeclareContextSlot...
-%SetProperty(this.__proto__, "x", "1234", NONE);
+%SetProperty(this.__proto__, "x", 1234, NONE);
 assertEquals(1234, x);
 eval("with({}) { var x = 5678; }");
 assertEquals(5678, x);
 
-%SetProperty(this.__proto__, "y", "1234", NONE);
+%SetProperty(this.__proto__, "y", 1234, NONE);
 assertEquals(1234, y);
 eval("with({}) { const y = 5678; }");
 assertEquals(5678, y);
 
-%SetProperty(this.__proto__, "z", "1234", READ_ONLY);
+%SetProperty(this.__proto__, "z", 1234, READ_ONLY);
 assertEquals(1234, z);
 eval("with({}) { var z = 5678; }");
 assertEquals(5678, z);
 
-%SetProperty(this.__proto__, "w", "1234", READ_ONLY);
+%SetProperty(this.__proto__, "w", 1234, READ_ONLY);
 assertEquals(1234, w);
 eval("with({}) { const w = 5678; }");
 assertEquals(5678, w);