Fixes for -Wunused-function on Linux, Android and ChromeOS

chrome/browser/chromeos/login/login_display_host_impl.cc

Index: chrome/browser/chromeos/login/login_display_host_impl.cc
diff --git a/chrome/browser/chromeos/login/login_display_host_impl.cc b/chrome/browser/chromeos/login/login_display_host_impl.cc
index 61965c412681f10456fd8d12790a5604e4ac5c5a..ac337c7181d49177bf63ea0d249bb953074656e1 100644
--- a/chrome/browser/chromeos/login/login_display_host_impl.cc
+++ b/chrome/browser/chromeos/login/login_display_host_impl.cc
@@ -150,10 +150,6 @@ void DetermineAndSaveHardwareKeyboard(const std::string& locale,
   }
 }
 
-ui::Layer* GetLayer(views::Widget* widget) {
-  return widget->GetNativeView()->layer();
-}
-
 // A class to observe an implicit animation and invokes the callback after the
 // animation is completed.
 class AnimationObserver : public ui::ImplicitAnimationObserver {