Revert r42156, r42157, r42160. Allow dynamic switching in and out of sidetabs...

chrome/browser/gtk/browser_window_gtk.cc

 // Copyright (c) 2010 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/gtk/browser_window_gtk.h"
 
 #include <gdk/gdkkeysyms.h>
 
 #include <string>
 
@@ skipping 1026 matching lines @@
 }
 
 void BrowserWindowGtk::Copy() {
   DoCutCopyPaste(this, &RenderViewHost::Copy, "copy-clipboard");
 }
 
 void BrowserWindowGtk::Paste() {
   DoCutCopyPaste(this, &RenderViewHost::Paste, "paste-clipboard");
 }
 
-void BrowserWindowGtk::ToggleTabStripMode() {
-  NOTIMPLEMENTED();
-}
-
 void BrowserWindowGtk::ConfirmBrowserCloseWithPendingDownloads() {
   new DownloadInProgressDialogGtk(browser());
 }
 
 void BrowserWindowGtk::Observe(NotificationType type,
                                const NotificationSource& source,
                                const NotificationDetails& details) {
   switch (type.value) {
     case NotificationType::BOOKMARK_BAR_VISIBILITY_PREF_CHANGED:
       MaybeShowBookmarkBar(browser_->GetSelectedTabContents(), true);
@@ skipping 998 matching lines @@
   // are taken from the WMs' source code.
   return (wm_name == "Blackbox" ||
           wm_name == "compiz" ||
           wm_name == "e16" ||  // Enlightenment DR16
           wm_name == "KWin" ||
           wm_name == "Metacity" ||
           wm_name == "Mutter" ||
           wm_name == "Openbox" ||
           wm_name == "Xfwm4");
 }