Revert 284850 "aura: Use PlatformWindow from WindowTreeHostWin."

trunk/src/ui/platform_window/win/win_window.h

Index: trunk/src/ui/platform_window/win/win_window.h
===================================================================
--- trunk/src/ui/platform_window/win/win_window.h	(revision 284904)
+++ trunk/src/ui/platform_window/win/win_window.h	(working copy)
@@ -72,15 +72,6 @@
   DISALLOW_COPY_AND_ASSIGN(WinWindow);
 };
 
-namespace test {
-
-// Set true to let WindowTreeHostWin use a popup window
-// with no frame/title so that the window size and test's
-// expectations matches.
-WIN_WINDOW_EXPORT void SetUsePopupAsRootWindowForTest(bool use);
-
-}  // namespace test
-
 }  // namespace ui
 
 #endif  // UI_PLATFORM_WINDOW_WIN_WIN_WINDOW_H_