Fixing chained syntax parsing when params are at the end of configured path (issue427041)

[johnfargo]

Reviewers: shindig.remailer_gmail.com, zhoresh,

Description:
The DefaultProxyUriManagerTest implementation was also not using the
process() method to verify parsing behavior, as it ought to have.
Changing the logic surfaced the issue.
Thanks to Ziv Horesh for taking notice.

Please review this at http://codereview.appspot.com/427041/show

Affected files:
   
java/gadgets/src/main/java/org/apache/shindig/gadgets/uri/DefaultProxyUriManager.java
   
java/gadgets/src/test/java/org/apache/shindig/gadgets/uri/DefaultProxyUriManagerTest.java