mus: Use the new drag API to implement tab dragging in chrome.

ui/views/widget/widget_unittest.cc

 // 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.
 
 #include <algorithm>
 #include <memory>
 #include <set>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 917 matching lines @@
   EXPECT_TRUE(widget_bounds_changed());
   reset();
 
   // Resize to the same thing while shown does nothing.
   widget->SetSize(gfx::Size(170, 100));
   EXPECT_FALSE(widget_bounds_changed());
   reset();
 
   // Move, but don't change the size.
   widget->SetBounds(gfx::Rect(110, 110, 170, 100));
-  // Currently fails on Mus. http://crbug.com/622575.
-  if (IsMus())
-    EXPECT_FALSE(widget_bounds_changed());
-  else
-    EXPECT_TRUE(widget_bounds_changed());
+  EXPECT_TRUE(widget_bounds_changed());
   reset();
 
   // Moving to the same place does nothing.
   widget->SetBounds(gfx::Rect(110, 110, 170, 100));
   EXPECT_FALSE(widget_bounds_changed());
   reset();
 
   // No bounds change when closing.
   widget->CloseNow();
   EXPECT_FALSE(widget_bounds_changed());
@@ skipping 2848 matching lines @@
                              CreateParams(Widget::InitParams::TYPE_WINDOW),
                              Widget::InitParams::TRANSLUCENT_WINDOW);
   EXPECT_EQ(IsNativeWindowTransparent(widget.GetNativeWindow()),
             widget.ShouldWindowContentsBeTransparent());
 }
 
 #endif  // !defined(OS_CHROMEOS)
 
 }  // namespace test
 }  // namespace views