Multipart representation creation crashes when an "optional" field has no value specified

[Leonard Richardson]

Adding this line to one of the sample WADL files will make the tests fail.

=== modified file 'src/wadllib/tests/data/multipart-binary-wadl.xml'
--- src/wadllib/tests/data/multipart-binary-wadl.xml 2009-05-06 16:37:44 +0000
+++ src/wadllib/tests/data/multipart-binary-wadl.xml 2009-09-15 16:33:40 +0000
@@ -12,6 +12,7 @@
       <request>
           <representation mediaType="multipart/form-data">
             <param style="plain" name="text_field" required="true" />
+ <param style="plain" name="optional_field" />
             <param style="plain" name="binary_field" type="binary"
                    required="true" />
           </representation>

The code in bind() tries to get a value for every single parameter defined in the representation, even optional ones. If you didn't specify a value for the parameter, bind() crashes.

This should be simple to fix.