Widget::ShouldUseNativeFrame is now meaningful on Linux.

ui/views/widget/desktop_aura/desktop_root_window_host_x11.h

 // Copyright (c) 2012 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 UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_X11_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_X11_H_
 
 #include <X11/extensions/shape.h>
 #include <X11/Xlib.h>
 
@@ skipping 98 matching lines @@
   virtual void SetAlwaysOnTop(bool always_on_top) OVERRIDE;
   virtual bool IsAlwaysOnTop() const OVERRIDE;
   virtual bool SetWindowTitle(const base::string16& title) OVERRIDE;
   virtual void ClearNativeFocus() OVERRIDE;
   virtual Widget::MoveLoopResult RunMoveLoop(
       const gfx::Vector2d& drag_offset,
       Widget::MoveLoopSource source,
       Widget::MoveLoopEscapeBehavior escape_behavior) OVERRIDE;
   virtual void EndMoveLoop() OVERRIDE;
   virtual void SetVisibilityChangedAnimationsEnabled(bool value) OVERRIDE;
-  virtual bool ShouldUseNativeFrame() OVERRIDE;
+  virtual bool ShouldUseNativeFrame() const OVERRIDE;
+  virtual bool ShouldWindowContentsBeTransparent() const OVERRIDE;
   virtual void FrameTypeChanged() OVERRIDE;
   virtual NonClientFrameView* CreateNonClientFrameView() OVERRIDE;
   virtual void SetFullscreen(bool fullscreen) OVERRIDE;
   virtual bool IsFullscreen() const OVERRIDE;
   virtual void SetOpacity(unsigned char opacity) OVERRIDE;
   virtual void SetWindowIcons(const gfx::ImageSkia& window_icon,
                               const gfx::ImageSkia& app_icon) OVERRIDE;
   virtual void InitModalType(ui::ModalType modal_type) OVERRIDE;
   virtual void FlashFrame(bool flash_frame) OVERRIDE;
   virtual void OnRootViewLayout() const OVERRIDE;
@@ skipping 41 matching lines @@
   // detect that they're there.
   bool IsWindowManagerPresent();
 
   // Sends a message to the x11 window manager, enabling or disabling the
   // states |state1| and |state2|.
   void SetWMSpecState(bool enabled, ::Atom state1, ::Atom state2);
 
   // Checks if the window manager has set a specific state.
   bool HasWMSpecProperty(const char* property) const;
 
+  // Sets whether the window's borders are provided by the window manager.
+  void SetUseNativeFrame(bool use_native_frame);
+
   // Called when another DRWHL takes capture, or when capture is released
   // entirely.
   void OnCaptureReleased();
 
   // Dispatches a mouse event, taking mouse capture into account. If a
   // different host has capture, we translate the event to its coordinate space
   // and dispatch it to that host instead.
   void DispatchMouseEvent(ui::MouseEvent* event);
 
   // Dispatches a touch event, taking capture into account. If a different host
@@ skipping 49 matching lines @@
   // The window manager state bits.
   std::set< ::Atom> window_properties_;
 
   // Local flag for fullscreen state to avoid a state mismatch between
   // server and local window_properties_ during app-initiated fullscreen.
   bool is_fullscreen_;
 
   // True if the window should stay on top of most other windows.
   bool is_always_on_top_;
 
+  // True if the window has title-bar / borders provided by the window manager.
+  bool use_native_frame_;
+
   // We are owned by the RootWindow, but we have to have a back pointer to it.
   aura::RootWindow* root_window_;
 
   scoped_ptr<DesktopDispatcherClient> dispatcher_client_;
 
   DesktopDragDropClientAuraX11* drag_drop_client_;
 
   // Current Aura cursor.
   gfx::NativeCursor current_cursor_;
 
@@ skipping 32 matching lines @@
   scoped_ptr<X11ScopedCapture> x11_capture_;
 
   base::string16 window_title_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopWindowTreeHostX11);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_ROOT_WINDOW_HOST_X11_H_