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

test/mjsunit/harmony/proxies-symbols.js

Index: test/mjsunit/harmony/proxies-symbols.js
diff --git a/test/mjsunit/harmony/proxies-symbols.js b/test/mjsunit/harmony/proxies-symbols.js
index 52353c036d4a4c25b6b47b52df8f82dde0f3d1f3..35e8a8fb5fc76380cd5e0957cc282c8b0a2b828d 100644
--- a/test/mjsunit/harmony/proxies-symbols.js
+++ b/test/mjsunit/harmony/proxies-symbols.js
@@ -31,8 +31,10 @@
 // Helper.
 
 function TestWithProxies(test, x, y, z) {
-  test(Proxy.create, x, y, z)
-  test(function(h) {return Proxy.createFunction(h, function() {})}, x, y, z)
+  test(function(h) { return new Proxy({}, h) }, x, y, z)
+  test(function(h) {
+    return Proxy.createFunction(h, function() {})
+  }, x, y, z)
 }