Windows: Add DirectWrite font cache support (issue #1652)

libcef/browser/browser_main_win.cc

@@ -9,6 +9,28 @@
 #include "libcef/browser/browser_host_impl.h"
 #include "libcef/browser/browser_main.h"
 
+#include "chrome/common/chrome_utility_messages.h"
+#include "content/public/browser/utility_process_host.h"
+#include "content/public/browser/utility_process_host_client.h"
+#include "content/public/common/dwrite_font_platform_win.h"
+#include "grit/cef_strings.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/gfx/win/direct_write.h"
+
+namespace {
+
+void ExecuteFontCacheBuildTask(const base::FilePath& path) {
+  base::WeakPtr<content::UtilityProcessHost> utility_process_host(
+      content::UtilityProcessHost::Create(NULL, NULL)->AsWeakPtr());
+  utility_process_host->SetName(l10n_util::GetStringUTF16(
+      IDS_UTILITY_PROCESS_FONT_CACHE_BUILDER_NAME));
+  utility_process_host->DisableSandbox();
+  utility_process_host->Send(
+      new ChromeUtilityHostMsg_BuildDirectWriteFontCache(path));
+}
+
+}  // namespace
+
 void CefBrowserMainParts::PlatformInitialize() {
   HRESULT res;
 
@@ -28,5 +50,38 @@ void CefBrowserMainParts::PlatformInitialize() {
   CefBrowserHostImpl::RegisterWindowClass();
 }
 
-void CefBrowserMainParts::PlatformCleanup() {
+void CefBrowserMainParts::PlatformPreMainMessageLoopRun() {
+  // From ChromeBrowserMainPartsWin::PostProfileInit().
+  // DirectWrite support is mainly available on Windows 7 and up.
+  if (gfx::win::ShouldUseDirectWrite()) {
+    const base::FilePath& cache_path = global_browser_context_->GetPath();
+    if (cache_path.empty())
+      return;
+
+    const base::FilePath& font_cache_path =
+        cache_path.AppendASCII(content::kFontCacheSharedSectionName);
+    // This function will create a read only section if cache file exists
+    // otherwise it will spawn utility process to build cache file, which will
+    // be used during next browser start/postprofileinit.
+    if (!content::LoadFontCache(font_cache_path)) {
+      // We delay building of font cache until first startup page loads.
+      // During first renderer start there are lot of things happening
+      // simultaneously some of them are:
+      // - Renderer is going through all font files on the system to create
+      //   a font collection.
+      // - Renderer loading up startup URL, accessing HTML/JS File cache,
+      //   net activity etc.
+      // - Extension initialization.
+      // We delay building of cache mainly to avoid parallel font file
+      // loading along with Renderer. Some systems have significant number of
+      // font files which takes long time to process.
+      // Related information is at http://crbug.com/436195.
+      const int kBuildFontCacheDelaySec = 30;
+      content::BrowserThread::PostDelayedTask(
+          content::BrowserThread::IO,
+          FROM_HERE,
+          base::Bind(ExecuteFontCacheBuildTask, font_cache_path),
+          base::TimeDelta::FromSeconds(kBuildFontCacheDelaySec));
+    }
+  }
 }