Ruby 1.9 compat: declare utf-8 file encoding

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8789 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/test/core_ext/string_ext_test.rb

@@ -1,3 +1,4 @@
+# encoding: utf-8
 require 'date'
 require 'abstract_unit'
 require 'inflector_test_cases'

activesupport/test/json/encoding_test.rb

@@ -1,3 +1,4 @@
+# encoding: utf-8
 require 'abstract_unit'
 
 class TestJSONEncoding < Test::Unit::TestCase

activesupport/test/multibyte_chars_test.rb

@@ -1,3 +1,4 @@
+# encoding: utf-8
 require 'abstract_unit'
 
 if RUBY_VERSION < '1.9'

activesupport/test/multibyte_handler_test.rb

@@ -1,3 +1,4 @@
+# encoding: utf-8
 require 'abstract_unit'
 
 if RUBY_VERSION < '1.9'