Make <webview> use out-of-process iframe architecture.

extensions/renderer/guest_view/extensions_iframe_guest_view_request.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extensions/renderer/guest_view/extensions_iframe_guest_view_request.h"
+
+#include "components/guest_view/renderer/guest_view_container.h"
+#include "content/public/renderer/render_frame.h"
+#include "extensions/common/guest_view/extensions_guest_view_messages.h"
+
+namespace extensions {
+
+GuestViewAttachIframeRequest::GuestViewAttachIframeRequest(
+    guest_view::GuestViewContainer* container,
+    int render_frame_routing_id,
+    int guest_instance_id,
+    scoped_ptr<base::DictionaryValue> params,
+    v8::Local<v8::Function> callback,
+    v8::Isolate* isolate)
+    : GuestViewRequest(container, callback, isolate),
+      render_frame_routing_id_(render_frame_routing_id),
+      guest_instance_id_(guest_instance_id),
+      params_(params.Pass()) {
+}
+
+GuestViewAttachIframeRequest::~GuestViewAttachIframeRequest() {
+}
+
+void GuestViewAttachIframeRequest::PerformRequest() {
+  DCHECK(container()->render_frame());
+
+  container()->render_frame()->Send(
+      new ExtensionsGuestViewHostMsg_AttachToEmbedderFrame(
+          render_frame_routing_id_, container()->element_instance_id(),
+          guest_instance_id_, *params_));
+}
+
+void GuestViewAttachIframeRequest::HandleResponse(const IPC::Message& message) {
+  ExtensionsGuestViewMsg_AttachToEmbedderFrame_ACK::Param param;
+  bool message_read_status =
+      ExtensionsGuestViewMsg_AttachToEmbedderFrame_ACK::Read(&message, &param);
+  DCHECK(message_read_status);
+
+  ExecuteCallbackIfAvailable(0, nullptr);
+}
+
+}  // namespace extensions