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

content/common/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/common/font_warmup_win.h"
 
 #include <dwrite.h>
 #include <stdint.h>
 #include <map>
 
 #include "base/debug/alias.h"
 #include "base/files/file_path.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/numerics/safe_conversions.h"
 #include "base/numerics/safe_math.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/synchronization/lock.h"
 #include "base/sys_byteorder.h"
 #include "base/trace_event/trace_event.h"
 #include "base/win/iat_patch_function.h"
 #include "base/win/windows_version.h"
 #include "content/public/common/dwrite_font_platform_win.h"
+#include "ppapi/shared_impl/proxy_lock.h"
 #include "skia/ext/fontmgr_default_win.h"
 #include "skia/ext/refptr.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"
 #include "ui/gfx/hud_font.h"
 
 namespace content {
 
@@ skipping 212 matching lines @@
   CHECK(g_warmup_fontmgr);
   int weight = log_font->lfWeight;
   if (weight == FW_DONTCARE)
     weight = SkFontStyle::kNormal_Weight;
 
   SkFontStyle style(weight, log_font->lfWidth,
                     log_font->lfItalic ? SkFontStyle::kItalic_Slant
                                        : SkFontStyle::kUpright_Slant);
 
   std::string family_name = base::WideToUTF8(log_font->lfFaceName);
+  ppapi::ProxyAutoLock lock;  // Needed for DirectWrite font proxy.
   return skia::AdoptRef(
       g_warmup_fontmgr->matchFamilyStyle(family_name.c_str(), style));
 }
 
 HDC WINAPI CreateCompatibleDCPatch(HDC dc_handle) {
   scoped_refptr<FakeGdiObject> ret =
       g_fake_gdi_object_factory.Get().Create(kFakeDCMagic);
   return static_cast<HDC>(ret->handle());
 }
 
@@ skipping 211 matching lines @@
 
     PatchDWriteFactory(factory);
 
     blink::WebFontRendering::setDirectWriteFactory(factory);
     g_warmup_fontmgr = SkFontMgr_New_DirectWrite(factory);
   }
   return g_warmup_fontmgr;
 }
 
 GdiFontPatchData* PatchGdiFontEnumeration(const base::FilePath& path) {
-  // We assume the fontmgr is already warmed up before calling this.
-  DCHECK(g_warmup_fontmgr);
+  if (content::ShouldUseDirectWriteFontProxyFieldTrial()) {

[fdoray, 2015/12/30 01:15:08]

// If the font cache is used, |g_warmup_fontmgr| is expected to be initialized
// by GetPreSandboxWarmupFontMgr before this function is called. If the font
// proxy is used, |g_warmup_fontmgr| is initialized when this function is
// called. This function is never called more than once per process.
if (content::ShouldUseDirectWriteFontProxyFieldTrial()) {
  DCHECK(!g_warmup_fontmgr);
  g_warmup_fontmgr = SkFontMgr_New_DirectWrite();
}
DCHECK(g_warmup_fontmgr);

Can you confirm that the comment I wrote is right? If PatchGdiFontEnumeration is
called multiple times, the previous value of |g_warmup_fontmgr| is leaked.

[Ilya Kulshin, 2015/12/30 01:59:46]

Good point about the leak. From tracing the code it looks like it's actually
called at least once per plugin, so I'll add a check to only initialize it if
it's not initialized already. 

+    g_warmup_fontmgr = SkFontMgr_New_DirectWrite();
+  } else {
+    // We assume the fontmgr is already warmed up before calling this.
+    DCHECK(g_warmup_fontmgr);
+  }
   return new GdiFontPatchDataImpl(path);
 }
 
 size_t GetEmulatedGdiHandleCountForTesting() {
   return g_fake_gdi_object_factory.Get().GetObjectCount();
 }
 
 void ResetEmulatedGdiHandlesForTesting() {
   g_fake_gdi_object_factory.Get().ResetObjectHandles();
 }
@@ skipping 13 matching lines @@
   // down for the CC HUD code, so use the same one here. Note that we don't use
   // a monospace as would be nice in an attempt to avoid a small startup time
   // regression, see http://crbug.com/463613.
   skia::RefPtr<SkTypeface> hud_typeface = skia::AdoptRef(
       GetPreSandboxWarmupFontMgr()->legacyCreateTypeface("Times New Roman", 0));
   DoPreSandboxWarmupForTypeface(hud_typeface.get());
   gfx::SetHudTypeface(hud_typeface);
 }
 
 }  // namespace content