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

third_party/WebKit/Source/platform/fonts/FontCache.h

 /*
  * Copyright (C) 2006, 2008 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2007-2008 Torch Mobile, Inc.
  *
  * 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.
@@ skipping 102 matching lines @@
   void invalidate();
 
   SkFontMgr* fontManager() { return m_fontManager.get(); }
   static void setFontManager(const sk_sp<SkFontMgr>&);
 
 #if !OS(MACOSX)
   static const AtomicString& systemFontFamily();
 #else
   static const AtomicString& legacySystemFontFamily();
 #endif
-#if OS(LINUX)
+#if OS(LINUX) || OS(ANDROID)
   static void setSystemFontFamily(const char*);
 #endif
 
 #if OS(WIN)
   static bool antialiasedTextEnabled() { return s_antialiasedTextEnabled; }
   static bool lcdTextEnabled() { return s_lcdTextEnabled; }
   static float deviceScaleFactor() { return s_deviceScaleFactor; }
   static void setAntialiasedTextEnabled(bool enabled) {
     s_antialiasedTextEnabled = enabled;
   }
@@ skipping 134 matching lines @@
   WTF_MAKE_NONCOPYABLE(FontCachePurgePreventer);
 
  public:
   FontCachePurgePreventer() { FontCache::fontCache()->disablePurging(); }
   ~FontCachePurgePreventer() { FontCache::fontCache()->enablePurging(); }
 };
 
 }  // namespace blink
 
 #endif