Disable Win32k renderer lockdown if DirectWrite is disabled.

content/public/common/content_switches.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 "content/public/common/content_switches.h"
 
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
+#if defined(OS_WIN)
+#include "base/win/windows_version.h"
+#include "ui/gfx/switches.h"
+#endif
 
 namespace switches {
 
 // The number of MSAA samples for canvas2D. Requires MSAA support by GPU to
 // have an effect. 0 disables MSAA.
 const char kAcceleratedCanvas2dMSAASampleCount[] = "canvas-msaa-sample-count";
 
 // By default, file:// URIs cannot read other file:// URIs. This is an
 // override for developers who need the old behavior for testing.
 const char kAllowFileAccessFromFiles[]      = "allow-file-access-from-files";
@@ skipping 935 matching lines @@
 // clashes between different instances of Chrome.
 const char kFontCacheSharedMemSuffix[] = "font-cache-shared-mem-suffix";
 #endif
 
 #if defined(ENABLE_PLUGINS)
 // Enables the plugin power saver feature.
 const char kEnablePluginPowerSaver[] = "enable-plugin-power-saver";
 #endif
 
 #if defined(OS_WIN)
-bool IsWin32kRendererLockdownEnabled() {
+bool IsWin32kRendererLockdownEnabled(bool ignore_directwrite) {

[cpu_(ooo_6.6-7.5), 2015/01/22 01:22:02]

not loving this contract, I mean interface.

   const std::string group_name =
       base::FieldTrialList::FindFullName("Win32kLockdown");
+  if (base::win::GetVersion() < base::win::VERSION_WIN8)
+    return false;
   const base::CommandLine* cmd_line = base::CommandLine::ForCurrentProcess();
+  if (!ignore_directwrite && cmd_line->HasSwitch(switches::kDisableDirectWrite))
+    return false;
   if (cmd_line->HasSwitch(kEnableWin32kRendererLockDown))
     return true;
   if (cmd_line->HasSwitch(kDisableWin32kRendererLockDown))
     return false;
   // Default.
   return group_name == "Enabled";
 }
 #endif
 
 // Don't dump stuff here, follow the same order as the header.
 
 }  // namespace switches