WidgetDelegateView is its own contents view.

chrome/browser/ui/views/ime/ime_window_view.cc

 // Copyright 2016 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/ui/views/ime/ime_window_view.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/ui/views/ime/ime_window_frame_view.h"
 #include "content/public/browser/web_contents.h"
 #include "ui/gfx/image/image.h"
@@ skipping 126 matching lines @@
   }
 }
 
 void ImeWindowView::OnTitlebarPointerCaptureLost() {
   if (dragging_state_ == DragState::ACTIVE_DRAG) {
     GetWidget()->SetBounds(bounds_on_drag_start_);
     EndDragging();
   }
 }
 
-views::View* ImeWindowView::GetContentsView() {
-  return this;
-}
-
 views::NonClientFrameView* ImeWindowView::CreateNonClientFrameView(
     views::Widget* widget) {
   ImeWindowFrameView* frame_view = new ImeWindowFrameView(
       this, ime_window_->mode());
   frame_view->Init();
   return frame_view;
 }
 
 bool ImeWindowView::CanActivate() const {
   return false;
@@ skipping 32 matching lines @@
 ImeWindowFrameView* ImeWindowView::GetFrameView() const {
   return static_cast<ImeWindowFrameView*>(
       window_->non_client_view()->frame_view());
 }
 
 void ImeWindowView::EndDragging() {
   dragging_state_ = DragState::NO_DRAG;
 }
 
 }  // namespace ui