Make bottom corners of panels not rounded on GTK.

chrome/browser/ui/gtk/browser_window_gtk.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 CHROME_BROWSER_UI_GTK_BROWSER_WINDOW_GTK_H_
 #define CHROME_BROWSER_UI_GTK_BROWSER_WINDOW_GTK_H_
 #pragma once
 
 #include <gtk/gtk.h>
 
@@ skipping 244 matching lines @@
   virtual void DestroyBrowser() OVERRIDE;
 
   // Returns an instance of |BrowserTitlebar| to be used for this window.
   virtual BrowserTitlebar* CreateBrowserTitlebar();
 
   // Checks to see if the mouse pointer at |x|, |y| is over the border of the
   // custom frame (a spot that should trigger a window resize). Returns true if
   // it should and sets |edge|.
   virtual bool GetWindowEdge(int x, int y, GdkWindowEdge* edge);
 
+  // Returns the window shape for the window with |width| and |height|.
+  // The caller is responsible for destroying the region if non-null region is
+  // returned.
+  virtual GdkRegion* GetWindowShape(int width, int height) const;
+
+  // Draws the border, including resizable corners, for the custom frame.
+  virtual void DrawCustomFrameBorder(GtkWidget* widget);
+
   virtual bool HandleTitleBarLeftMousePress(GdkEventButton* event,
                                             guint32 last_click_time,
                                             gfx::Point last_click_position);
 
   // Returns true if handled.
   virtual bool HandleWindowEdgeLeftMousePress(GtkWindow* window,
                                               GdkWindowEdge edge,
                                               GdkEventButton* event);
 
   // Save the window position in the prefs.
@@ skipping 279 matching lines @@
   scoped_ptr<FullscreenExitBubbleGtk> fullscreen_exit_bubble_;
 
   FullscreenExitBubbleType fullscreen_exit_bubble_type_;
 
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserWindowGtk);
 };
 
 #endif  // CHROME_BROWSER_UI_GTK_BROWSER_WINDOW_GTK_H_