Revert of Remove font cache code

content/child/font_warmup_win.cc

Index: content/child/font_warmup_win.cc
diff --git a/content/child/font_warmup_win.cc b/content/child/font_warmup_win.cc
index e3c07115ff09b669a0a3fd07e27a72823efea13c..33d18075f642e518a148ade4e5808f83d791a259 100644
--- a/content/child/font_warmup_win.cc
+++ b/content/child/font_warmup_win.cc
@@ -22,9 +22,12 @@
 #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"
 
@@ -94,6 +97,36 @@
                                        void* in_message_attributes,
                                        void* time_out) {
   return STATUS_ACCESS_DENIED;
+}
+
+// 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);
+    base::debug::Alias(&load_library_get_last_error);
+    CHECK(false);
+  }
+
+  PatchServiceManagerCalls();
+
+  DWriteCreateFactoryProc dwrite_create_factory_proc =
+      reinterpret_cast<DWriteCreateFactoryProc>(
+          GetProcAddress(dwrite_dll, "DWriteCreateFactory"));
+  // TODO(scottmg): Temporary code to track crash in http://crbug.com/387867.
+  if (!dwrite_create_factory_proc) {
+    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))));
 }
 
 // Class to fake out a DC or a Font object. Maintains a reference to a
@@ -413,9 +446,30 @@
   DCHECK(patched == 0);
 }
 
+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);
+
+    g_warmup_fontmgr =
+        SkFontMgr_New_DirectWrite(factory, GetCustomFontCollection(factory));
+    blink::WebFontRendering::setSkiaFontManager(g_warmup_fontmgr);
+  }
+  return g_warmup_fontmgr;
+}
+
 GdiFontPatchData* PatchGdiFontEnumeration(const base::FilePath& path) {
-  if (!g_warmup_fontmgr)
+  if (ShouldUseDirectWriteFontProxyFieldTrial() && !g_warmup_fontmgr)
     g_warmup_fontmgr = SkFontMgr_New_DirectWrite();
+  // If not using the font proxy, we assume |g_warmup_fontmgr| is already
+  // initialized before this function is called.
   DCHECK(g_warmup_fontmgr);
   return new GdiFontPatchDataImpl(path);
 }
@@ -432,4 +486,19 @@
   g_warmup_fontmgr = fontmgr;
 }
 
+void WarmupDirectWrite() {
+  TRACE_EVENT0("startup", "content::WarmupDirectWrite");
+
+  // The objects used here are intentionally not freed as we want the Skia
+  // code to use these objects after warmup.
+  SetDefaultSkiaFactory(GetPreSandboxWarmupFontMgr());
+
+  // We need to warm up *some* font for DirectWrite. 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());
+}
+
 }  // namespace content