[WIP] Fire a theme changed notification when device scan completes

chrome/browser/themes/theme_service.h

Index: chrome/browser/themes/theme_service.h
diff --git a/chrome/browser/themes/theme_service.h b/chrome/browser/themes/theme_service.h
index d8e02262b2cd2f37e4adc6f59b65403a0894882e..4ea0b7ff90ba9cb9844475761b1d18996231bff2 100644
--- a/chrome/browser/themes/theme_service.h
+++ b/chrome/browser/themes/theme_service.h
@@ -21,6 +21,7 @@
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "ui/base/theme_provider.h"
+#include "ui/events/devices/input_device_event_observer.h"
 
 class CustomThemeSupplier;
 class BrowserThemePack;
@@ -60,6 +61,7 @@ extern "C" NSString* const kBrowserThemeDidChangeNotification;
 
 class ThemeService : public base::NonThreadSafe,
                      public content::NotificationObserver,
+                     public ui::InputDeviceEventObserver,
                      public KeyedService {
  public:
   // Public constants used in ThemeService and its subclasses:
@@ -78,6 +80,9 @@ class ThemeService : public base::NonThreadSafe,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override;
 
+  // ui::InputDeviceEventObserver:
+  void OnDeviceListsComplete() override;
+
   // Set the current theme to the theme defined in |extension|.
   // |extension| must already be added to this profile's
   // ExtensionService.