Improve WorkspaceWindowResizer::CompleteDrag() so that the function moves the window to a root windo

ash/wm/workspace/workspace_window_resizer.h

Index: ash/wm/workspace/workspace_window_resizer.h
diff --git a/ash/wm/workspace/workspace_window_resizer.h b/ash/wm/workspace/workspace_window_resizer.h
index 258d89c58567e30beb550fec331b585e4f814086..51e06ab9fcd5b1675b8b773576b5e03dae550855 100644
--- a/ash/wm/workspace/workspace_window_resizer.h
+++ b/ash/wm/workspace/workspace_window_resizer.h
@@ -181,6 +181,9 @@ class ASH_EXPORT WorkspaceWindowResizer : public WindowResizer {
   // the screen.
   int num_mouse_moves_since_bounds_change_;
 
+  // The mouse location passed to Drag().
+  gfx::Point last_mouse_location_;
+
   DISALLOW_COPY_AND_ASSIGN(WorkspaceWindowResizer);
 };