Delete some dead code

runtime/lib/string_patch.dart

Index: runtime/lib/string_patch.dart
===================================================================
--- runtime/lib/string_patch.dart	(revision 23830)
+++ runtime/lib/string_patch.dart	(working copy)
@@ -467,75 +467,6 @@
 
   String toLowerCase() native "String_toLowerCase";
 
-  // Implementations of Strings methods follow below.
-  static String join(Iterable<String> strings, String separator) {
-    bool first = true;
-    List<String> stringsList = <String>[];
-    for (String string in strings) {
-      if (first) {
-        first = false;
-      } else {
-        stringsList.add(separator);
-      }
-
-      if (string is! String) {
-        throw new ArgumentError(Error.safeToString(string));
-      }
-      stringsList.add(string);
-    }
-    return concatAll(stringsList);
-  }
-
-  static String concatAll(Iterable<String> strings) {
-    _ObjectArray stringsArray;
-    final len = strings.length;
-    bool isOneByteString = true;
-    int totalLength = 0;
-    if (strings._cid == _ObjectArray._clCId) {
-      stringsArray = strings;
-      for (int i = 0; i < len; i++) {
-        var string = strings[i];
-        if (string._cid == _OneByteString._classId) {
-          totalLength += string.length;
-        } else {
-          isOneByteString = false;
-          if (string is! String) throw new ArgumentError(string);
-        }
-      }
-    } else {
-      // Copy into an _ObjectArray.
-      stringsArray = new _ObjectArray(len);
-      int i = 0;
-      for (int i = 0; i < len; i++) {
-        var string = strings[i];
-        if (string._cid == _OneByteString.clCid) {
-          totalLength += s.length;
-        } else {
-          isOneByteString = false;
-          if (string is! String) throw new ArgumentError(string);
-        }
-        stringsArray[i++] = string;
-      }
-    }
-    if (isOneByteString) {
-      return _OneByteString._concatAll(stringsArray, totalLength);
-    }
-    return _concatAllNative(stringsArray);
-  }
-
-  static String _concatAll(_ObjectArray<String> strings) {
-    int totalLength = 0;
-    final stringsLength = strings.length;
-    for (int i = 0; i < stringsLength; i++) {
-      var e = strings[i];
-      if (e._cid != _OneByteString._classId) {
-        return _concatAllNative(strings);
-      }
-      totalLength += e.length;
-    }
-    return _OneByteString._concatAll(strings, totalLength);
-  }
-
   // Call this method if not all list elements are OneByteString-s.
   static String _concatAllNative(_ObjectArray<String> strings)
       native "Strings_concatAll";