Remove remainder of Athena related code from Chrome

chrome/browser/ui/views/athena/athena_util.h

Index: chrome/browser/ui/views/athena/athena_util.h
diff --git a/chrome/browser/ui/views/athena/athena_util.h b/chrome/browser/ui/views/athena/athena_util.h
deleted file mode 100644
index a5b2178bc8e7708e9db4d18c3ca28b560dcd59f1..0000000000000000000000000000000000000000
--- a/chrome/browser/ui/views/athena/athena_util.h
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef CHROME_BROWSER_UI_VIEWS_ATHENA_ATHENA_UTIL_H_
-#define CHROME_BROWSER_UI_VIEWS_ATHENA_ATHENA_UTIL_H_
-
-namespace aura {
-class Window;
-}
-
-namespace content {
-class WebContents;
-}
-
-// Returns the web content associated with the window.
-content::WebContents* GetWebContentsForWindow(aura::Window* owner_window);
-
-#endif  // CHROME_BROWSER_UI_VIEWS_ATHENA_ATHENA_UTIL_H_