Allow the default generic font family settings to find the first available font

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

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 12 matching lines @@
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "platform/fonts/GenericFontFamilySettings.h"
 
+#include "platform/fonts/FontCache.h"
+
 namespace blink {
 
 GenericFontFamilySettings::GenericFontFamilySettings(
     const GenericFontFamilySettings& other)
     : m_standardFontFamilyMap(other.m_standardFontFamilyMap),
       m_serifFontFamilyMap(other.m_serifFontFamilyMap),
       m_fixedFontFamilyMap(other.m_fixedFontFamilyMap),
       m_sansSerifFontFamilyMap(other.m_sansSerifFontFamilyMap),
       m_cursiveFontFamilyMap(other.m_cursiveFontFamilyMap),
       m_fantasyFontFamilyMap(other.m_fantasyFontFamilyMap),
@@ skipping 25 matching lines @@
   } else if (it != fontMap.end() && it->value == family) {
     return;
   } else {
     fontMap.set(static_cast<int>(script), family);
   }
 }
 
 const AtomicString& GenericFontFamilySettings::genericFontFamilyForScript(
     const ScriptFontFamilyMap& fontMap,
     UScriptCode script) const {
-  ScriptFontFamilyMap::const_iterator it =
-      fontMap.find(static_cast<int>(script));
-  if (it != fontMap.end())
+  ScriptFontFamilyMap::iterator it =
+      const_cast<ScriptFontFamilyMap&>(fontMap).find(static_cast<int>(script));
+  if (it != fontMap.end()) {
+    // Replace with the first available font if it starts with ",".
+    if (!it->value.isEmpty() && it->value[0] == ',')
+      it->value = AtomicString(FontCache::firstAvailableOrFirst(it->value));
     return it->value;
+  }
   if (script != USCRIPT_COMMON)
     return genericFontFamilyForScript(fontMap, USCRIPT_COMMON);
   return emptyAtom;
 }
 
 const AtomicString& GenericFontFamilySettings::standard(
     UScriptCode script) const {
   return genericFontFamilyForScript(m_standardFontFamilyMap, script);
 }
 
@@ skipping 85 matching lines @@
   m_standardFontFamilyMap.clear();
   m_serifFontFamilyMap.clear();
   m_fixedFontFamilyMap.clear();
   m_sansSerifFontFamilyMap.clear();
   m_cursiveFontFamilyMap.clear();
   m_fantasyFontFamilyMap.clear();
   m_pictographFontFamilyMap.clear();
 }
 
 }  // namespace blink