Use DirectWrite to populate list of avalible fonts

content/public/renderer/render_font_warmup_win.cc

 // Copyright 2014 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/renderer/render_font_warmup_win.h"
 
 #include <dwrite.h>
 
 #include "base/debug/alias.h"
 #include "base/logging.h"
 #include "third_party/WebKit/public/web/win/WebFontRendering.h"
 #include "third_party/skia/include/core/SkPaint.h"
 #include "third_party/skia/include/ports/SkFontMgr.h"
 #include "third_party/skia/include/ports/SkTypeface_win.h"
 
 namespace content {
 
-namespace {
-
 SkFontMgr* g_warmup_fontmgr = NULL;

[scottmg, 2014/06/26 20:13:38]

I don't think it's a great idea to make another of these. If you can't use the
SkFontMgr, I would instead save off the created factory below and have a getter
for that.

[eae, 2014/06/26 20:58:24]

That makes sense. Any idea where this code should live then? Probably not in
public/renderer...

[scottmg, 2014/06/26 21:05:17]

Yeah, I think I wouldn't bother sharing with this code now.

There's factory creation in Skia, since it's happening in browser, we don't do
any of that there yet (UI is still GDI rendered).

I _think_ (though am not certain) that code in skia/ext can use
third_party/skia/src/utils/win/SkDWrite.cpp, so sk_get_dwrite_factory() there
might be the easiest, if you just have the content/common code call a utility
function there.

 
 // Windows-only DirectWrite support. These warm up the DirectWrite paths
 // before sandbox lock down to allow Skia access to the Font Manager service.
 void CreateDirectWriteFactory(IDWriteFactory** factory) {
   typedef decltype(DWriteCreateFactory)* DWriteCreateFactoryProc;
   HMODULE dwrite_dll = LoadLibraryW(L"dwrite.dll");
   // TODO(scottmg): Temporary code to track crash in http://crbug.com/387867.
   if (!dwrite_dll) {
     DWORD load_library_get_last_error = GetLastError();
     base::debug::Alias(&dwrite_dll);
@@ skipping 10 matching lines @@
     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))));
 }
 
-}  // namespace
-
 void DoPreSandboxWarmupForTypeface(SkTypeface* typeface) {
   SkPaint paint_warmup;
   paint_warmup.setTypeface(typeface);
   wchar_t glyph = L'S';
   paint_warmup.measureText(&glyph, 2);
 }
 
 SkFontMgr* GetPreSandboxWarmupFontMgr() {
   if (!g_warmup_fontmgr) {
     IDWriteFactory* factory;
     CreateDirectWriteFactory(&factory);
     blink::WebFontRendering::setDirectWriteFactory(factory);
     g_warmup_fontmgr = SkFontMgr_New_DirectWrite(factory);
   }
   return g_warmup_fontmgr;
 }
 
 }  // namespace content