Fixes bug in dragging tabs. Specifically if you only have one window...

chrome/browser/views/tabs/tab.cc

 // Copyright (c) 2006-2008 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.h"
 
 #include "base/gfx/size.h"
 #include "chrome/common/gfx/chrome_canvas.h"
 #include "chrome/common/gfx/path.h"
 #include "chrome/common/l10n_util.h"
@@ skipping 144 matching lines @@
 
 bool Tab::HasHitTestMask() const {
   return true;
 }
 
 void Tab::GetHitTestMask(gfx::Path* mask) const {
   MakePathForTab(mask);
 }
 
 bool Tab::OnMousePressed(const views::MouseEvent& event) {
-  if (event.IsLeftMouseButton()) {
+  if (event.IsOnlyLeftMouseButton()) {
     // Store whether or not we were selected just now... we only want to be
     // able to drag foreground tabs, so we don't start dragging the tab if
     // it was in the background.
     bool just_selected = !IsSelected();
     if (just_selected)
       delegate_->SelectTab(this);
     delegate_->MaybeStartDrag(this, event);
   }
   return true;
 }
@@ skipping 97 matching lines @@
 
   // Close out the path.
   path->lineTo(0, h);
   path->close();
 }
 
 void Tab::ContextMenuClosed() {
   delegate()->StopAllHighlighting();
   menu_controller_ = NULL;
 }