Match language tags by prefix on Android.

src/ports/SkFontMgr_android.cpp

Index: src/ports/SkFontMgr_android.cpp
diff --git a/src/ports/SkFontMgr_android.cpp b/src/ports/SkFontMgr_android.cpp
index 2865d800b7c34c0d40d7bdb09cbe52aadf375702..c527551575f7b3ddd3cfe626751101102cab3792 100644
--- a/src/ports/SkFontMgr_android.cpp
+++ b/src/ports/SkFontMgr_android.cpp
@@ -353,7 +353,7 @@ static SkTypeface_AndroidSystem* find_family_style_character(
         SkFontStyleSet_Android* family = fallbackNameToFamilyMap[i].styleSet;
         SkAutoTUnref<SkTypeface_AndroidSystem> face(family->matchStyle(style));
 
-        if (!langTag.isEmpty() && langTag != face->fLang.getTag()) {
+        if (!langTag.isEmpty() && !face->fLang.getTag().startsWith(langTag.c_str())) {
             continue;
         }