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

extensions/renderer/dispatcher.cc

Index: extensions/renderer/dispatcher.cc
diff --git a/extensions/renderer/dispatcher.cc b/extensions/renderer/dispatcher.cc
index b40e77e78d377c5f3791a04deee6c37cda28a3b9..2b3e6cb6a6f99860a31f535e6a52a2aaacce9be9 100644
--- a/extensions/renderer/dispatcher.cc
+++ b/extensions/renderer/dispatcher.cc
@@ -99,6 +99,8 @@
 #include "ui/base/layout.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "v8/include/v8.h"
+#include "extensions/common/guest_view/guest_view_messages.h"
+#include "extensions/renderer/guest_view/extensions_guest_view_container.h"
 
 using base::UserMetricsAction;
 using blink::WebDataSource;
@@ -813,6 +815,8 @@ bool Dispatcher::OnControlMessageReceived(const IPC::Message& message) {
   IPC_MESSAGE_HANDLER(ExtensionMsg_ClearTabSpecificPermissions,
                       OnClearTabSpecificPermissions)
   IPC_MESSAGE_HANDLER(ExtensionMsg_UsingWebRequestAPI, OnUsingWebRequestAPI)
+  IPC_MESSAGE_HANDLER_GENERIC(GuestViewMsg_ContentWindowReady,
+                              OnGuestContentWindowReady(message))
   IPC_MESSAGE_FORWARD(ExtensionMsg_WatchPages,
                       content_watcher_.get(),
                       ContentWatcher::OnWatchPages)
@@ -1142,6 +1146,18 @@ void Dispatcher::OnUsingWebRequestAPI(bool webrequest_used) {
   webrequest_used_ = webrequest_used;
 }
 
+void Dispatcher::OnGuestContentWindowReady(const IPC::Message& message) {
+  GuestViewMsg_ContentWindowReady::Param param;
+  bool read_status = GuestViewMsg_ContentWindowReady::Read(&message, &param);
+  DCHECK(read_status);
+  int element_instance_id = get<0>(param);
+  ExtensionsGuestViewContainer* container =
+      ExtensionsGuestViewContainer::FromID(
+          element_instance_id);
+  DCHECK(container);
+  container->OnMessageReceived(message);
+}
+
 void Dispatcher::OnUserScriptsUpdated(
       const std::set<std::string>& changed_extensions,
       const std::vector<UserScript*>& scripts) {