c++ / mojo changes for 'external window mode'

services/ui/ws/window_tree_host_factory.cc

Index: services/ui/ws/window_tree_host_factory.cc
diff --git a/services/ui/ws/window_tree_host_factory.cc b/services/ui/ws/window_tree_host_factory.cc
index 1efbf9b5a429e200be7e13eacc01f56704830a3a..81be2847afaff68e442597118d8131a9a6095896 100644
--- a/services/ui/ws/window_tree_host_factory.cc
+++ b/services/ui/ws/window_tree_host_factory.cc
@@ -8,6 +8,7 @@
 #include "services/ui/ws/display.h"
 #include "services/ui/ws/display_binding.h"
 #include "services/ui/ws/window_server.h"
+#include "services/ui/ws/window_tree.h"
 
 namespace ui {
 namespace ws {
@@ -44,5 +45,26 @@ void WindowTreeHostFactory::CreateWindowTreeHost(
   ws_display->Init(metrics, std::move(display_binding));
 }
 
+void WindowTreeHostFactory::CreatePlatformWindow(
+    mojom::WindowTreeHostRequest tree_host_request,
+    Id transport_window_id) {
+  WindowTree* tree = window_server_->GetTreeForExternalWindowMode();
+  tree->WillCreateRootDisplay(transport_window_id);
+
+  Display* ws_display = new Display(window_server_);
+
+  std::unique_ptr<DisplayBindingImpl> display_binding(
+      new DisplayBindingImpl(std::move(tree_host_request), ws_display, user_id_,
+                             nullptr, window_server_));
+
+  // Provide an initial size for the WindowTreeHost.
+  display::ViewportMetrics metrics;
+  metrics.bounds_in_pixels = gfx::Rect(1024, 768);
+  metrics.device_scale_factor = 1.0f;
+  metrics.ui_scale_factor = 1.0f;
+
+  ws_display->Init(metrics, std::move(display_binding));
+}
+
 }  // namespace ws
 }  // namespace ui