Fix chromium-style warning after https://codereview.chromium.org/1639623003/

ui/gfx/screen_win_unittest.cc

 // Copyright 2015 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/gfx/screen_win.h"
 
 #include <windows.h>
 #include <inttypes.h>
 #include <stddef.h>
 
@@ skipping 34 matching lines @@
 class TestScreenWin : public gfx::ScreenWin {
  public:
   TestScreenWin(const std::vector<gfx::win::DisplayInfo>& display_infos,
                 const std::vector<MONITORINFOEX>& monitor_infos,
                 const std::unordered_map<HWND, gfx::Rect>& hwnd_map)
       : monitor_infos_(monitor_infos),
         hwnd_map_(hwnd_map) {
     UpdateFromDisplayInfos(display_infos);
   }
 
-  ~TestScreenWin() = default;
+  ~TestScreenWin() override = default;
 
  protected:
   // gfx::ScreenWin:
   HWND GetHWNDFromNativeView(NativeView window) const override {
     // NativeView is only used as an identifier in this tests, so interchange
     // NativeView with an HWND for convenience.
     return reinterpret_cast<HWND>(window);
   }
 
   NativeWindow GetNativeWindowFromHWND(HWND hwnd) const override {
@@ skipping 33 matching lines @@
     EXPECT_NE(largest_area, 0);
     return candidate;
   }
 
   MONITORINFOEX MonitorInfoFromWindow(HWND hwnd, DWORD default_options)
       const override {
     auto search = hwnd_map_.find(hwnd);
     if (search != hwnd_map_.end())
       return MonitorInfoFromScreenRect(search->second);
 
-    EXPECT_EQ(default_options, MONITOR_DEFAULTTOPRIMARY);
+    EXPECT_EQ(default_options, static_cast<DWORD>(MONITOR_DEFAULTTOPRIMARY));
     for (const auto& monitor_info : monitor_infos_) {
       if (monitor_info.rcMonitor.left == 0 &&
           monitor_info.rcMonitor.top == 0) {
         return monitor_info;
       }
     }
     NOTREACHED();
     return monitor_infos_[0];
   }
 
@@ skipping 524 matching lines @@
             screen->GetDisplayMatching(gfx::Rect(10139, 2299, 100, 100)));
 }
 
 TEST_F(ScreenWinTestTwoDisplays2x1xVirtualized, GetPrimaryDisplay) {
   gfx::Screen* screen = GetScreen();
   gfx::Display primary = screen->GetPrimaryDisplay();
   EXPECT_EQ(gfx::Point(0, 0), primary.bounds().origin());
 }
 
 }  // namespace gfx