Add support for virtual displays

ui/display/chromeos/update_display_configuration_task.h

Index: ui/display/chromeos/update_display_configuration_task.h
diff --git a/ui/display/chromeos/update_display_configuration_task.h b/ui/display/chromeos/update_display_configuration_task.h
index 7b8272e750411b2f65531bba52998a4f635c5778..c3c9ba2277e055c9fede79e4243b4eaa3c1869a7 100644
--- a/ui/display/chromeos/update_display_configuration_task.h
+++ b/ui/display/chromeos/update_display_configuration_task.h
@@ -35,6 +35,12 @@ class DISPLAY_EXPORT UpdateDisplayConfigurationTask {
                                  const ResponseCallback& callback);
   ~UpdateDisplayConfigurationTask();
 
+  // The pointers to the DisplaySnapshots in this vector are owned by
+  // DisplayConfigurator.
+  void set_virtual_display_snapshots(std::vector<DisplaySnapshot*> snapshots) {
+    virtual_display_snapshots_ = snapshots;
+  }
+
   void Run();
 
  private:
@@ -92,6 +98,9 @@ class DISPLAY_EXPORT UpdateDisplayConfigurationTask {
   // List of updated displays.
   std::vector<DisplaySnapshot*> cached_displays_;
 
+  // Vector of unowned VirtualDisplaySnapshots to be added when doing the task.
+  std::vector<DisplaySnapshot*> virtual_display_snapshots_;
+
   gfx::Size framebuffer_size_;
 
   scoped_ptr<ConfigureDisplaysTask> configure_task_;