win: fix narrowing warning on vs2015

ui/platform_window/win/win_window.cc

 // Copyright 2014 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 "ui/platform_window/win/win_window.h"
 
 #include "base/profiler/scoped_tracker.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
 #include "ui/gfx/win/msg_util.h"
@@ skipping 97 matching lines @@
 void WinWindow::MoveCursorTo(const gfx::Point& location) {}
 
 void WinWindow::ConfineCursorToBounds(const gfx::Rect& bounds) {
 }
 
 LRESULT WinWindow::OnMouseRange(UINT message, WPARAM w_param, LPARAM l_param) {
   // TODO(vadimt): Remove ScopedTracker below once crbug.com/440919 is fixed.
   tracked_objects::ScopedTracker tracking_profile(
       FROM_HERE_WITH_EXPLICIT_FUNCTION("440919 WinWindow::OnMouseRange"));
 
-  MSG msg = { hwnd(), message, w_param, l_param, GetMessageTime(),
+  MSG msg = { hwnd(), message, w_param, l_param,
+              static_cast<DWORD>(GetMessageTime()),

[sky, 2015/04/13 22:51:50]

Wow, weird that GetMessageTime() isn't typed to DWORD.

               { CR_GET_X_LPARAM(l_param), CR_GET_Y_LPARAM(l_param) } };
   MouseEvent event(msg);
   if (IsMouseEventFromTouch(message))
     event.set_flags(event.flags() | EF_FROM_TOUCH);
   if (!(event.flags() & ui::EF_IS_NON_CLIENT))
     delegate_->DispatchEvent(&event);
   SetMsgHandled(event.handled());
   return 0;
 }
 
@@ skipping 84 matching lines @@
 
 namespace test {
 
 // static
 void SetUsePopupAsRootWindowForTest(bool use) {
   use_popup_as_root_window_for_test = use;
 }
 
 }  // namespace test
 }  // namespace ui