Add support for a virtual display on ChromeOS

ui/display/chromeos/display_util.h

Index: ui/display/chromeos/display_util.h
diff --git a/ui/display/chromeos/display_util.h b/ui/display/chromeos/display_util.h
index 8df778d840aa02dafee44e58aaa848281504ed42..baf2a25aa9fa6df7b635b82c2e7f4c6afbc0a246 100644
--- a/ui/display/chromeos/display_util.h
+++ b/ui/display/chromeos/display_util.h
@@ -27,6 +27,11 @@ int DISPLAY_EXPORT GetDisplayPower(
     chromeos::DisplayPowerState state,
     std::vector<bool>* display_power);
 
+// Returns whether the DisplayConnectionType |type| is a physically connected
+// display. Currently DISPLAY_CONNECTION_TYPE_VIRTUAL and
+// DISPLAY_CONNECTION_TYPE_NETWORK return true. All other types return false.
+bool IsPhysicalDisplayType(ui::DisplayConnectionType type);
+
 }  // namespace ui
 
 #endif  // UI_DISPLAY_CHROMEOS_DISPLAY_UTIL_H_