Use v8::Context::NewRemoteContext in RemoteWindowProxy.

third_party/WebKit/Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 Google Inc. 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
@@ skipping 8932 matching lines @@
   lastChild(mainFrame())->swap(remoteFrame);
   remoteFrame->setReplicatedOrigin(SecurityOrigin::createUnique());
   v8::Local<v8::Value> remoteWindowProperty =
       mainFrame()->executeScriptAndReturnValue(
           WebScriptSource("window[2].foo"));
   EXPECT_TRUE(remoteWindowProperty.IsEmpty());
 
   reset();
 }
 
+TEST_F(WebFrameSwapTest, RemoteWindowToString) {
+  v8::HandleScope scope(v8::Isolate::GetCurrent());
+
+  FrameTestHelpers::TestWebRemoteFrameClient remoteClient;
+  WebRemoteFrame* remoteFrame = remoteClient.frame();
+  lastChild(mainFrame())->swap(remoteFrame);
+  remoteFrame->setReplicatedOrigin(SecurityOrigin::createUnique());
+  v8::Local<v8::Value> exception = mainFrame()->executeScriptAndReturnValue(
+      WebScriptSource("try { '' + window[2]; } catch (e) { e; }"));

[jochen (gone - plz use gerrit), 2017/03/23 18:27:48]

Object.prototype.toString.call(window[2]) should work, no?

[dcheng, 2017/03/23 18:31:51]

Hmm... that's one version I forgot to try. I'll upload a followup CL if this
makes a difference.

+  ASSERT_FALSE(exception.IsEmpty());
+  EXPECT_STREQ(
+      "SecurityError: Blocked a frame with origin \"http://internal.test\" "
+      "from accessing a cross-origin frame.",
+      *v8::String::Utf8Value(exception));
+
+  reset();
+}
+
 // TODO(alexmos, dcheng): This test and some other OOPIF tests use
 // very little of the test fixture support in WebFrameSwapTest.  We should
 // clean these tests up.
 TEST_F(WebFrameSwapTest, FramesOfRemoteParentAreIndexable) {
   v8::HandleScope scope(v8::Isolate::GetCurrent());
 
   FrameTestHelpers::TestWebRemoteFrameClient remoteClient;
   WebRemoteFrame* remoteParentFrame = remoteClient.frame();
   mainFrame()->swap(remoteParentFrame);
   remoteParentFrame->setReplicatedOrigin(SecurityOrigin::createUnique());
@@ skipping 2466 matching lines @@
   EXPECT_FALSE(testSelectAll("<textarea></textarea>"));
   EXPECT_TRUE(testSelectAll("<textarea>nonempty</textarea>"));
   EXPECT_FALSE(testSelectAll("<input>"));
   EXPECT_TRUE(testSelectAll("<input value='nonempty'>"));
   // TODO(amaralp): Empty contenteditable should not have select all enabled.
   EXPECT_TRUE(testSelectAll("<div contenteditable></div>"));
   EXPECT_TRUE(testSelectAll("<div contenteditable>nonempty</div>"));
 }
 
 }  // namespace blink