Add safety move for TLD lookup string

git-svn-id: https://cld2.googlecode.com/svn/trunk@71 b252ecd4-b096-bf77-eb8e-91563289f87e

internal/compact_lang_det_hint_code.cc

@@ -1448,6 +1448,8 @@ void SetCLDTLDHint(const char* tld, CLDLangPriors* langpriors) {
   if (len > 3) {return;}        // Ignore if more than three letters
   char local_tld[4];
   strncpy(local_tld, tld, len);
+  local_tld[3] = '\0';          // Safety move
+  // Lowercase
   for (int i = 0; i < len; ++i) {local_tld[i] |= 0x20;}
   const TLDLookup* entry = DoTLDLookup(local_tld,
                                        kCLDTLDHintTable,