Remove unsafe registry APIs from base::win::RegKey

ui/gfx/font_render_params_win.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/gfx/font_render_params.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 13 matching lines @@
   for (int i = 0; EnumDisplayDevices(nullptr, i, &display_device, 0); ++i) {
     // TODO(scottmg): We only support the primary device currently.
     if (display_device.StateFlags & DISPLAY_DEVICE_PRIMARY_DEVICE) {
       base::FilePath trimmed =
           base::FilePath(display_device.DeviceName).BaseName();
       base::win::RegKey key(
           HKEY_LOCAL_MACHINE,
           (L"SOFTWARE\\Microsoft\\Avalon.Graphics\\" + trimmed.value()).c_str(),
           KEY_READ);
       DWORD pixel_structure;
-      if (key.ReadValueDW(L"PixelStructure", &pixel_structure) ==
-          ERROR_SUCCESS) {
+      if (key.Valid() && key.ReadValueDW(L"PixelStructure", &pixel_structure) ==
+                             ERROR_SUCCESS) {
         if (pixel_structure == 1)
           return FontRenderParams::SUBPIXEL_RENDERING_RGB;
         if (pixel_structure == 2)
           return FontRenderParams::SUBPIXEL_RENDERING_BGR;
       }
       break;
     }
   }
 
   // No explicit ClearType settings, default to RGB.
@@ skipping 59 matching lines @@
 
 FontRenderParams GetFontRenderParams(const FontRenderParamsQuery& query,
                                      std::string* family_out) {
   if (family_out)
     NOTIMPLEMENTED();
   // Customized font rendering settings are not supported, only defaults.
   return CachedFontRenderParams::GetInstance()->GetParams();
 }
 
 }  // namespace gfx