Fallback on system locale for font selection

third_party/WebKit/Source/platform/fonts/FontDescription.cpp

Index: third_party/WebKit/Source/platform/fonts/FontDescription.cpp
diff --git a/third_party/WebKit/Source/platform/fonts/FontDescription.cpp b/third_party/WebKit/Source/platform/fonts/FontDescription.cpp
index 2008681e0ccd0973e5bae08faa3d38b697a41d62..12a30d774a8d79424e84ec6f0049b3d665886764 100644
--- a/third_party/WebKit/Source/platform/fonts/FontDescription.cpp
+++ b/third_party/WebKit/Source/platform/fonts/FontDescription.cpp
@@ -29,6 +29,7 @@
 
 #include "platform/fonts/FontDescription.h"
 
+#include "platform/Language.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "wtf/StringHasher.h"
 #include "wtf/text/AtomicStringHash.h"
@@ -125,8 +126,13 @@ FontDescription::VariantLigatures FontDescription::variantLigatures() const
 static const AtomicString& defaultLocale()
 {
     DEFINE_STATIC_LOCAL(AtomicString, locale, ());
-    if (locale.isNull())
-        locale = AtomicString("en");
+    if (locale.isNull()) {
+        AtomicString defaultLocale = defaultLanguage();
+        if (!defaultLocale.isEmpty())
+            locale = defaultLocale;
+        else
+            locale = AtomicString("en");
+    }
     return locale;
 }