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

content/ppapi_plugin/ppapi_plugin_main.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 "base/base_paths.h"
 #include "base/command_line.h"
 #include "base/debug/crash_logging.h"
 #include "base/debug/debugger.h"
 #include "base/files/file_path.h"
 #include "base/i18n/rtl.h"
 #include "base/message_loop/message_loop.h"
 #include "base/path_service.h"
 #include "base/threading/platform_thread.h"
 #include "build/build_config.h"
 #include "content/child/child_process.h"
 #include "content/common/content_constants_internal.h"
 #include "content/common/sandbox_linux/sandbox_linux.h"
 #include "content/ppapi_plugin/ppapi_thread.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/main_function_params.h"
 #include "content/public/plugin/content_plugin_client.h"
+#include "ipc/ipc_sender.h"
 #include "ppapi/proxy/plugin_globals.h"
 #include "ppapi/proxy/proxy_module.h"
 #include "ui/base/ui_base_switches.h"
 
 #if defined(OS_WIN)
 #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/dwrite_font_platform_win.h"
 #include "sandbox/win/src/sandbox.h"
 #include "third_party/WebKit/public/web/win/WebFontRendering.h"
 #include "third_party/skia/include/ports/SkTypeface_win.h"
 #include "ui/gfx/win/direct_write.h"
 #include "ui/gfx/win/dpi.h"
 #endif
 
 #if defined(OS_CHROMEOS)
 #include "base/files/file_util.h"
 #endif
@@ skipping 91 matching lines @@
 
   ChildProcess ppapi_process;
   ppapi_process.set_main_thread(
       new PpapiThread(parameters.command_line, false));  // Not a broker.
 
 #if defined(OS_WIN)
   if (!base::win::IsUser32AndGdi32Available())
     gfx::win::MaybeInitializeDirectWrite();
   bool use_direct_write = gfx::win::IsDirectWriteEnabled();
   if (use_direct_write) {
-    WarmupDirectWrite();
+    if (content::ShouldUseDirectWriteFontProxyFieldTrial()) {

[jam, 2016/01/11 05:05:45]

ditto and also below

[Ilya Kulshin, 2016/01/11 20:56:52]

Done.

+      InitializeDWriteFontProxy(
+          base::Bind(&ppapi::proxy::PluginGlobals::GetBrowserSender,
+                     base::Unretained(ppapi::proxy::PluginGlobals::Get())));
+    } else {
+      WarmupDirectWrite();
+    }
   } else {
     SkTypeface_SetEnsureLOGFONTAccessibleProc(SkiaPreCacheFont);
   }
 
   blink::WebFontRendering::setUseDirectWrite(use_direct_write);
   blink::WebFontRendering::setDeviceScaleFactor(gfx::GetDPIScale());
 #endif
 
   main_message_loop.Run();
+
+#if defined(OS_WIN)
+  if (content::ShouldUseDirectWriteFontProxyFieldTrial())
+    UninitializeDWriteFontProxy();
+#endif
   return 0;
 }
 
 }  // namespace content