Move the ShouldUseDirectWrite function from sandbox_win.cc/.h to ui/gfx/win/dpi.cc/.h.

ui/gfx/win/dpi.cc

 // Copyright (c) 2012 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/win/dpi.h"
 
 #include <windows.h>
 #include "base/command_line.h"
+#include "base/metrics/field_trial.h"
 #include "base/win/scoped_hdc.h"
 #include "base/win/windows_version.h"
 #include "base/win/registry.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/switches.h"
 #include "ui/gfx/point_conversions.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/size_conversions.h"
 
 namespace {
@@ skipping 202 matching lines @@
 
 int GetSystemMetricsInDIP(int metric) {
   return static_cast<int>(GetSystemMetrics(metric) /
       GetDeviceScaleFactor() + 0.5);
 }
 
 bool IsDeviceScaleFactorSet() {
   return g_device_scale_factor != 0.0f;
 }
 
+bool ShouldUseDirectWrite() {
+  // If the flag is currently on, and we're on Win7 or above, we enable
+  // DirectWrite. Skia does not require the additions to DirectWrite in QFE
+  // 2670838, but a simple 'better than XP' check is not enough.
+  if (base::win::GetVersion() < base::win::VERSION_WIN7)
+    return false;
+
+  base::win::OSInfo::VersionNumber os_version =
+      base::win::OSInfo::GetInstance()->version_number();
+  if ((os_version.major == 6) && (os_version.minor == 1)) {
+    // We can't use DirectWrite for pre-release versions of Windows 7.
+    if (os_version.build < 7600)
+      return false;
+  }
+  // If forced off, don't use it.
+  const base::CommandLine& command_line =
+      *base::CommandLine::ForCurrentProcess();
+  if (command_line.HasSwitch(switches::kDisableDirectWrite))
+    return false;
+
+  // Can't use GDI on HiDPI.
+  if (gfx::GetDPIScale() > 1.0f)
+    return true;
+
+  // Otherwise, check the field trial.
+  const std::string group_name =
+      base::FieldTrialList::FindFullName("DirectWrite");
+  return group_name != "Disabled";
+}
+
 }  // namespace win
 }  // namespace gfx