[runtime] support new Proxy() instead of Proxy.create and install getPrototypeOf trap

test/mjsunit/strong/load-proxy.js

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --harmony-proxies --strong-mode
 
 // Forwarding proxies adapted from proposal definition
 function handlerMaker1(obj) {
   return {
     getPropertyDescriptor: function(name) {
@@ skipping 32 matching lines @@
           result[name] = Object.getOwnPropertyDescriptor(obj, name);
         });
         return result;
       }
       // As long as obj is not frozen, the proxy won't allow itself to be fixed
       return undefined; // will cause a TypeError to be thrown
     }
   };
 }
 var baseObj = {};
-var proxy1 = Proxy.create(handlerMaker1(baseObj));
-var proxy2 = Proxy.create(handlerMaker2(baseObj));
+var proxy1 = new Proxy({}, handlerMaker1(baseObj));
+var proxy2 = new Proxy({}, handlerMaker2(baseObj));
 var childObj1 = { __proto__: proxy1 };
 var childObj2 = { __proto__: proxy2 };
 var childObjAccessor1 = { set foo(_){}, set "1"(_){}, __proto__: proxy1 };
 var childObjAccessor2 = { set foo(_){}, set "1"(_){}, __proto__: proxy2 };
 
 (function() {
   "use strong";
   // TODO(conradw): These asserts are sanity checking V8's proxy implementation.
   // Strong mode semantics for ES6 proxies still need to be explored.
   assertDoesNotThrow(function(){proxy1.foo});
@@ skipping 26 matching lines @@
   // assertThrows(function(){childObjAccessor1[1]}, TypeError);
   //
   // Object.freeze(proxy2);
   // assertThrows(function(){proxy2.foo}, TypeError);
   // assertThrows(function(){proxy2[1]}, TypeError);
   // assertThrows(function(){childObj2.foo}, TypeError);
   // assertThrows(function(){childObj2[1]}, TypeError);
   // assertThrows(function(){childObjAccessor2.foo}, TypeError);
   // assertThrows(function(){childObjAccessor2[1]}, TypeError);
 })();