Add logic to switch to DirectWrite font proxy via field trial.

content/renderer/renderer_main_platform_delegate_win.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/renderer/renderer_main_platform_delegate.h"
 
+#include <dwrite.h>
+
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
 #include "base/win/scoped_comptr.h"
 #include "base/win/win_util.h"
 #include "base/win/windows_version.h"
+#include "content/child/dwrite_font_proxy/dwrite_font_proxy_init_win.h"
 #include "content/common/font_warmup_win.h"
 #include "content/public/common/content_switches.h"
+#include "content/public/common/dwrite_font_platform_win.h"
 #include "content/public/common/injection_test_win.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/renderer/render_thread_impl.h"
 #include "sandbox/win/src/sandbox.h"
 #include "third_party/WebKit/public/web/WebRuntimeFeatures.h"
 #include "third_party/WebKit/public/web/win/WebFontRendering.h"
 #include "third_party/icu/source/i18n/unicode/timezone.h"
 #include "third_party/skia/include/ports/SkTypeface_win.h"
 #include "ui/gfx/win/direct_write.h"
 #include "ui/gfx/win/dpi.h"
 
-#include <dwrite.h>
-
 namespace content {
 namespace {
 
 // Windows-only skia sandbox support
 // These are used for GDI-path rendering.
 void SkiaPreCacheFont(const LOGFONT& logfont) {
   RenderThread* render_thread = RenderThread::Get();
   if (render_thread) {
     render_thread->PreCacheFont(logfont);
   }
 }
 
+// Helper function to cast RenderThread to IPC::Sender so we can Bind()
+// it.
+IPC::Sender* GetRenderThreadSender() {
+  return RenderThread::Get();
+}
+
 }  // namespace
 
 RendererMainPlatformDelegate::RendererMainPlatformDelegate(
     const MainFunctionParams& parameters)
         : parameters_(parameters),
           sandbox_test_module_(NULL) {
 }
 
 RendererMainPlatformDelegate::~RendererMainPlatformDelegate() {
 }
 
 void RendererMainPlatformDelegate::PlatformInitialize() {
   const base::CommandLine& command_line = parameters_.command_line;
 
   // Be mindful of what resources you acquire here. They can be used by
   // malicious code if the renderer gets compromised.
   bool no_sandbox = command_line.HasSwitch(switches::kNoSandbox);
 
   bool use_direct_write = gfx::win::ShouldUseDirectWrite();
   if (!no_sandbox) {
     // ICU DateFormat class (used in base/time_format.cc) needs to get the
     // Olson timezone ID by accessing the registry keys under
     // HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones.
     // After TimeZone::createDefault is called once here, the timezone ID is
     // cached and there's no more need to access the registry. If the sandbox
     // is disabled, we don't have to make this dummy call.
     scoped_ptr<icu::TimeZone> zone(icu::TimeZone::createDefault());
 
     if (use_direct_write) {
-      WarmupDirectWrite();
+      if (content::ShouldUseDirectWriteFontProxyFieldTrial())
+        InitializeDWriteFontProxy(base::Bind(&GetRenderThreadSender));
+      else
+        WarmupDirectWrite();
     } else {
       SkTypeface_SetEnsureLOGFONTAccessibleProc(SkiaPreCacheFont);
     }
   }
   blink::WebFontRendering::setUseDirectWrite(use_direct_write);
   blink::WebFontRendering::setDeviceScaleFactor(gfx::GetDPIScale());
 }
 
 void RendererMainPlatformDelegate::PlatformUninitialize() {
+  if (content::ShouldUseDirectWriteFontProxyFieldTrial())
+    UninitializeDWriteFontProxy();
 }
 
 bool RendererMainPlatformDelegate::EnableSandbox() {
   sandbox::TargetServices* target_services =
       parameters_.sandbox_info->target_services;
 
   if (target_services) {
     // Cause advapi32 to load before the sandbox is turned on.
     unsigned int dummy_rand;
     rand_s(&dummy_rand);
 
     target_services->LowerToken();
     return true;
   }
   return false;
 }
 
 }  // namespace content