Use ChildThreadImpl::thread_safe_sender in font proxy if available

content/child/dwrite_font_proxy/dwrite_font_proxy_init_win.cc

 // Copyright 2015 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/child/dwrite_font_proxy/dwrite_font_proxy_init_win.h"
 
 #include <dwrite.h>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 42 matching lines @@
     DWORD get_proc_address_get_last_error = GetLastError();
     base::debug::Alias(&dwrite_create_factory_proc);
     base::debug::Alias(&get_proc_address_get_last_error);
     CHECK(false);
   }
   CHECK(SUCCEEDED(dwrite_create_factory_proc(
       DWRITE_FACTORY_TYPE_ISOLATED, __uuidof(IDWriteFactory),
       reinterpret_cast<IUnknown**>(factory))));
 }
 
+// Needed as a function for Bind()
+IPC::Sender* GetSenderOverride() {
+  return g_sender_override;
+}
+
 }  // namespace
 
-void InitializeDWriteFontProxy() {
+void InitializeDWriteFontProxy(
+    const base::Callback<IPC::Sender*(void)>& sender) {
   mswr::ComPtr<IDWriteFactory> factory;
 
   CreateDirectWriteFactory(&factory);
 
   if (!g_font_collection) {
-    mswr::MakeAndInitialize<DWriteFontCollectionProxy>(
-        &g_font_collection, factory.Get(), g_sender_override);
+    if (g_sender_override) {
+      mswr::MakeAndInitialize<DWriteFontCollectionProxy>(
+          &g_font_collection, factory.Get(), base::Bind(&GetSenderOverride));
+    } else {
+      mswr::MakeAndInitialize<DWriteFontCollectionProxy>(&g_font_collection,
+                                                         factory.Get(), sender);
+    }
   }
 
   mswr::ComPtr<IDWriteFontFallback> font_fallback;
   mswr::ComPtr<IDWriteFactory2> factory2;
   if (SUCCEEDED(factory.As(&factory2)) && factory2.Get()) {
     mswr::MakeAndInitialize<FontFallback>(
         &font_fallback, g_font_collection.Get(), g_sender_override);
   }
 
   sk_sp<SkFontMgr> skia_font_manager(SkFontMgr_New_DirectWrite(
@@ skipping 21 matching lines @@
 void UninitializeDWriteFontProxy() {
   if (g_font_collection)
     g_font_collection->Unregister();
 }
 
 void SetDWriteFontProxySenderForTesting(IPC::Sender* sender) {
   g_sender_override = sender;
 }
 
 }  // namespace content