Implement the default tab opening behavior. Fix some linux build issues by adding missing includes.

chrome/browser/views/tabs/tab_overview_drag_controller.cc

 // Copyright (c) 2009 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.
 
 #include "chrome/browser/views/tabs/tab_overview_drag_controller.h"
 
 #include "chrome/browser/browser.h"
 #include "chrome/browser/browser_window.h"
 #include "chrome/browser/dock_info.h"
+#include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/browser/tabs/tab_strip_model.h"
 #include "chrome/browser/views/tabs/tab_overview_cell.h"
 #include "chrome/browser/views/tabs/tab_overview_controller.h"
 #include "chrome/browser/views/tabs/tab_overview_grid.h"
 #include "chrome/common/notification_service.h"
 #include "views/fill_layout.h"
 #include "views/view.h"
 #include "views/widget/root_view.h"
 #include "views/widget/widget_gtk.h"
 
@@ skipping 370 matching lines @@
                    Source<TabContents>(tab));
 
     // We need to be the delegate so we receive messages about stuff,
     // otherwise our dragged contents may be replaced and subsequently
     // collected/destroyed while the drag is in process, leading to
     // nasty crashes.
     original_delegate_ = tab->delegate();
     tab->set_delegate(this);
   }
 }