add customized printing setting for headless

headless/lib/headless_content_main_delegate.cc

Index: headless/lib/headless_content_main_delegate.cc
diff --git a/headless/lib/headless_content_main_delegate.cc b/headless/lib/headless_content_main_delegate.cc
index 9428908a6657555fd751c6f28ff32fdd3554a188..0139f8225355f3916add506c25acacfb4100870b 100644
--- a/headless/lib/headless_content_main_delegate.cc
+++ b/headless/lib/headless_content_main_delegate.cc
@@ -34,6 +34,12 @@
 #endif
 
 #if defined(OS_MACOSX)
+#include "base/mac/bundle_locations.h"
+#else
+#include "ui/base/ui_base_paths.h"
+#endif
+
+#if defined(OS_MACOSX)
 #include "components/crash/content/app/crashpad.h"
 #endif
 
@@ -244,6 +250,15 @@ void HeadlessContentMainDelegate::InitializeResourceBundle() {
   bool result = PathService::Get(base::DIR_MODULE, &dir_module);
   DCHECK(result);
 
+  // Override locale pak dir to 'headless_locales'.
+  base::FilePath locale_pak =
+      dir_module.Append(FILE_PATH_LITERAL("headless_locales"));
+#if defined(OS_MACOSX)
+  base::mac::SetOverrideFrameworkBundlePath(locale_pak);
+#else
+  PathService::Override(ui::DIR_LOCALES, locale_pak);
+#endif
+
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
   const std::string locale = command_line->GetSwitchValueASCII(switches::kLang);
   ui::ResourceBundle::InitSharedInstanceWithLocale(