only require redcloth/bluecloth if they are not already loaded [Rick]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4257 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

actionpack/lib/action_view/helpers/text_helper.rb

@@ -77,7 +77,7 @@ def word_wrap(text, line_width = 80)
       end
 
       begin
-        require_library_or_gem "redcloth"
+        require_library_or_gem "redcloth" unless Object.const_defined?(:RedCloth)
 
         # Returns the text with all the Textile codes turned into HTML-tags.
         # <i>This method is only available if RedCloth can be required</i>.
@@ -104,7 +104,7 @@ def textilize_without_paragraph(text)
       end
 
       begin
-        require_library_or_gem "bluecloth"
+        require_library_or_gem "bluecloth" unless Object.const_defined?(:BlueCloth)
 
         # Returns the text with all the Markdown codes turned into HTML-tags.
         # <i>This method is only available if BlueCloth can be required</i>.