Make HWNDMessageHandler subclass WindowImpl.

chrome/browser/ui/views/native_constrained_window_win.cc

 // Copyright (c) 2011 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/constrained_window_views.h"
 
 #include "ui/views/widget/native_widget_win.h"
 
 namespace {
 bool IsNonClientHitTestCode(UINT hittest) {
@@ skipping 16 matching lines @@
   // Overridden from NativeConstrainedWindow:
   virtual views::NativeWidget* AsNativeWidget() OVERRIDE {
     return this;
   }
 
   // Overridden from views::NativeWidgetWin:
   virtual void OnFinalMessage(HWND window) OVERRIDE {
     delegate_->OnNativeConstrainedWindowDestroyed();
     NativeWidgetWin::OnFinalMessage(window);
   }
-  virtual LRESULT OnMouseActivate(UINT message,
-                                  WPARAM w_param,
-                                  LPARAM l_param) OVERRIDE {
-    if (IsNonClientHitTestCode(static_cast<UINT>(LOWORD(l_param))))
+  virtual bool PreHandleMSG(UINT message,
+                            WPARAM w_param,
+                            LPARAM l_param,
+                            LRESULT* result) OVERRIDE {
+    if (message == WM_MOUSEACTIVATE &&
+        IsNonClientHitTestCode(static_cast<UINT>(LOWORD(l_param)))) {
       delegate_->OnNativeConstrainedWindowMouseActivate();
-    return NativeWidgetWin::OnMouseActivate(message, w_param, l_param);
+    }
+    return false;
   }
 
   NativeConstrainedWindowDelegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeConstrainedWindowWin);
 };
 
 ////////////////////////////////////////////////////////////////////////////////
 // NativeConstrainedWindow, public:
 
 // static
 NativeConstrainedWindow* NativeConstrainedWindow::CreateNativeConstrainedWindow(
     NativeConstrainedWindowDelegate* delegate) {
   return new NativeConstrainedWindowWin(delegate);
 }