Remove unused |context| from GetDefaultParent().

extensions/shell/browser/shell_desktop_controller_aura.h

 // 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 EXTENSIONS_SHELL_BROWSER_SHELL_DESKTOP_CONTROLLER_AURA_H_
 #define EXTENSIONS_SHELL_BROWSER_SHELL_DESKTOP_CONTROLLER_AURA_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 62 matching lines @@
 
   // DesktopController:
   gfx::Size GetWindowSize() override;
   AppWindow* CreateAppWindow(content::BrowserContext* context,
                              const Extension* extension) override;
   void AddAppWindow(gfx::NativeWindow window) override;
   void RemoveAppWindow(AppWindow* window) override;
   void CloseAppWindows() override;
 
   // aura::client::WindowParentingClient overrides:
-  aura::Window* GetDefaultParent(aura::Window* context,
-                                 aura::Window* window,
+  aura::Window* GetDefaultParent(aura::Window* window,
                                  const gfx::Rect& bounds) override;
 
 #if defined(OS_CHROMEOS)
   // chromeos::PowerManagerClient::Observer overrides:
   void PowerButtonEventReceived(bool down,
                                 const base::TimeTicks& timestamp) override;
 
   // display::DisplayConfigurator::Observer overrides.
   void OnDisplayModeChanged(
       const display::DisplayConfigurator::DisplayStateList& displays) override;
@@ skipping 51 matching lines @@
 
   // NativeAppWindow::Close() deletes the AppWindow.
   std::vector<AppWindow*> app_windows_;
 
   DISALLOW_COPY_AND_ASSIGN(ShellDesktopControllerAura);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_SHELL_BROWSER_SHELL_DESKTOP_CONTROLLER_AURA_H_