Set the font family for the "system-ui" generic font family on Linux

third_party/WebKit/Source/platform/fonts/linux/FontCacheLinux.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 16 matching lines @@
 #include "platform/fonts/FontPlatformData.h"
 #include "platform/fonts/SimpleFontData.h"
 #include "public/platform/linux/WebFallbackFont.h"
 #include "public/platform/linux/WebSandboxSupport.h"
 #include "public/platform/Platform.h"
 #include "ui/gfx/font_fallback_linux.h"
 #include "wtf/text/CString.h"
 
 namespace blink {
 
+AtomicString* FontCache::s_systemFontFamilyName = 0;
+
+// static
+const AtomicString& FontCache::systemFontFamily()
+{
+    return *s_systemFontFamilyName;
+}
+
+// static
+void FontCache::setSystemFontFamily(const char* familyName)
+{
+    s_systemFontFamilyName = new AtomicString(familyName);
+}
+
 FontCache::FontCache()
     : m_purgePreventCount(0)
 {
     if (s_staticFontManager) {
         adopted(s_staticFontManager);
         m_fontManager = sk_ref_sp(s_staticFontManager);
     } else {
         m_fontManager = nullptr;
     }
 }
@@ skipping 90 matching lines @@
 
     std::unique_ptr<FontPlatformData> platformData(new FontPlatformData(*substitutePlatformData));
     platformData->setSyntheticBold(shouldSetSyntheticBold);
     platformData->setSyntheticItalic(shouldSetSyntheticItalic);
     return fontDataFromFontPlatformData(platformData.get(), DoNotRetain);
 }
 
 #endif // !OS(ANDROID)
 
 } // namespace blink