Remove now-unnecessary wrappers around gfx::Screen::GetScreen()

extensions/shell/browser/shell_display_info_provider.cc

Index: extensions/shell/browser/shell_display_info_provider.cc
diff --git a/extensions/shell/browser/shell_display_info_provider.cc b/extensions/shell/browser/shell_display_info_provider.cc
index 32239ab0a26170d9276a2c5169712931e0e9adb7..18ee96782026ab55f6a0e3b0abc924494d136551 100644
--- a/extensions/shell/browser/shell_display_info_provider.cc
+++ b/extensions/shell/browser/shell_display_info_provider.cc
@@ -30,10 +30,6 @@ void ShellDisplayInfoProvider::UpdateDisplayUnitInfoForPlatform(
   }
 }
 
-gfx::Screen* ShellDisplayInfoProvider::GetActiveScreen() {
-  return NULL;
-}
-
 // static
 DisplayInfoProvider* DisplayInfoProvider::Create() {
   return new ShellDisplayInfoProvider();