Draw web content area correctly on a phantom window for window dragging

ash/wm/workspace/workspace_window_resizer_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 "ash/wm/workspace/workspace_window_resizer.h"
 
 #include "ash/screen_ash.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/test/ash_test_base.h"
@@ skipping 589 matching lines @@
     EXPECT_FALSE(resizer->snap_phantom_window_controller_.get());
     EXPECT_FALSE(resizer->drag_phantom_window_controller_.get());
 
     // The window spans both root windows.
     resizer->Drag(CalculateDragPoint(*resizer, 798, 10), 0);
     EXPECT_FALSE(resizer->snap_phantom_window_controller_.get());
     PhantomWindowController* controller =
         resizer->drag_phantom_window_controller_.get();
     ASSERT_TRUE(controller);
     EXPECT_EQ(PhantomWindowController::STYLE_WINDOW, controller->style());
+    EXPECT_EQ(resizer->layer_, controller->layer());
     // |window_| should be opaque since the pointer is still on the primary
     // root window. The phantom should be semi-transparent.
     EXPECT_FLOAT_EQ(1.0f, window_->layer()->opacity());
     EXPECT_GT(1.0f, controller->GetOpacity());
 
     // Enter the pointer to the secondary display.
     resizer->Drag(CalculateDragPoint(*resizer, 0, 610), 0);
     EXPECT_FALSE(resizer->snap_phantom_window_controller_.get());
     controller = resizer->drag_phantom_window_controller_.get();
     ASSERT_TRUE(controller);
@@ skipping 217 matching lines @@
   ASSERT_TRUE(resizer.get());
   // Ctrl + drag the window to new poistion by adding (10, 12) to its origin,
   // the window should move to the exact position.
   resizer->Drag(CalculateDragPoint(*resizer, 10, 12), 0);
   resizer->CompleteDrag(ui::EF_CONTROL_DOWN);
   EXPECT_EQ("106,124 320x160", window_->bounds().ToString());
 }
 
 }  // namespace test
 }  // namespace ash