Add PlatformScreenDelegate and start implementation.

services/ui/display/platform_screen_impl_ozone.cc

Index: services/ui/display/platform_screen_impl_ozone.cc
diff --git a/services/ui/display/platform_screen_impl_ozone.cc b/services/ui/display/platform_screen_impl_ozone.cc
index c4f1ada7c42de733cdd48d54424f1dc7f48f1bc0..8f7ba5477ab2a75069e836568f49942a277536db 100644
--- a/services/ui/display/platform_screen_impl_ozone.cc
+++ b/services/ui/display/platform_screen_impl_ozone.cc
@@ -45,9 +45,10 @@ void PlatformScreenImplOzone::Init() {
       ui::OzonePlatform::GetInstance()->CreateNativeDisplayDelegate(), false);
 }
 
-void PlatformScreenImplOzone::ConfigurePhysicalDisplay(
-    const PlatformScreen::ConfiguredDisplayCallback& callback) {
-  callback_ = callback;
+void PlatformScreenImplOzone::ConfigureDisplays(
+    PlatformScreenDelegate* delegate) {
+  DCHECK(delegate);
+  delegate_ = delegate;
 
   if (base::SysInfo::IsRunningOnChromeOS()) {
     display_configurator_.ForceInitialConfigure(kChromeOsBootColor);
@@ -96,7 +97,7 @@ void PlatformScreenImplOzone::OnDisplayModeChanged(
     // Keep track of what displays have already been added.
     displays_.insert(display->display_id());
 
-    callback_.Run(id, bounds);
+    delegate_->OnDisplayAdded(this, id, bounds);
   }
 
   DCHECK(displays_ == all_displays) << "Removing displays is not supported.";