Fix ambiguity in API if no matching system language is found

src/ports/SkFontConfigInterface_android.cpp

 
 /*
  * Copyright 2013 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkFontConfigInterface.h"
 #include "SkTypeface_android.h"
@@ skipping 495 matching lines @@
         // store the result for subsequent lookups
         fontRec.fTypeface = face;
     }
     SkASSERT(face);
     return face;
 }
 
 bool SkFontConfigInterfaceAndroid::getFallbackFamilyNameForChar(SkUnichar uni,
                                                                 const char* lang,
                                                                 SkString* name) {
-    FallbackFontList* fallbackFontList = this->findFallbackFontList(lang);
+    FallbackFontList* fallbackFontList = NULL;
+    const SkString langTag(lang);
+    if (langTag.isEmpty()) {
+        fallbackFontList = this->getCurrentLocaleFallbackFontList();
+    } else {
+        fallbackFontList = this->findFallbackFontList(langTag);
+    }
+
     for (int i = 0; i < fallbackFontList->count(); i++) {
         FamilyRecID familyRecID = fallbackFontList->getAt(i);
 
         // if it is not one of the accepted variants then move to the next family
         int32_t acceptedVariants = SkPaintOptionsAndroid::kDefault_Variant |
                                    SkPaintOptionsAndroid::kElegant_Variant;
         if (!(fFontFamilies[familyRecID].fPaintOptions.getFontVariant() & acceptedVariants)) {
             continue;
         }
 
@@ skipping 199 matching lines @@
         if (uBounds) {
             *uBounds = upperBounds;
         }
     }
     return currentTypeface;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 bool SkGetFallbackFamilyNameForChar(SkUnichar uni, SkString* name) {
-    SkString locale = SkFontConfigParser::GetLocale();
     SkFontConfigInterfaceAndroid* fontConfig = getSingletonInterface();
-    return fontConfig->getFallbackFamilyNameForChar(uni, locale.c_str(), name);
+    return fontConfig->getFallbackFamilyNameForChar(uni, NULL, name);
 }
 
 bool SkGetFallbackFamilyNameForChar(SkUnichar uni, const char* lang, SkString* name) {
     SkFontConfigInterfaceAndroid* fontConfig = getSingletonInterface();
     return fontConfig->getFallbackFamilyNameForChar(uni, lang, name);
 }
 
 void SkUseTestFontConfigFile(const char* mainconf, const char* fallbackconf,
                              const char* fontsdir) {
     gTestMainConfigFile = mainconf;
@@ skipping 170 matching lines @@
     return SkCreateTypefaceForScriptNG(getHBScriptFromHBScriptOld(script), style, fontVariant);
 }
 
 #endif
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkFontMgr* SkFontMgr::Factory() {
     return NULL;
 }