test rename overhaul: step 8 - language tests

tests/language/adjacent_string_literals_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 main() {
   testEmpty();
   testInterpolation();
   testMultiline();
 }
 
@@ skipping 64 matching lines @@
 a""" "b" "e");
   Expect.equals("a b e", """
 a""" " b" " e");
 
   Expect.equals("abe", """
 a""" """
 b""" """
 e""");
 }