Change declaration of ProxyBase#setRequestHeaders to throw GadgetException (issue1683050)

[janluehe]

Reviewers: dev-remailer_shindig.apache.org,

Description:
This patch changes the declaration of ProxyBase#setRequestHeaders to
throw a GadgetException, which makes it easier to override this method
and is also consistent with ProxyBase#setResponseHeaders, which already
declares to throw this kind of exception.

Please review this at http://codereview.appspot.com/1683050/show

Affected files:
   
java/gadgets/src/main/java/org/apache/shindig/gadgets/servlet/ProxyBase.java


Index:  
java/gadgets/src/main/java/org/apache/shindig/gadgets/servlet/ProxyBase.java
===================================================================
---  
java/gadgets/src/main/java/org/apache/shindig/gadgets/servlet/ProxyBase.java	 
(revision 957093)
+++  
java/gadgets/src/main/java/org/apache/shindig/gadgets/servlet/ProxyBase.java	 
(working copy)
@@ -147,7 +147,8 @@
     }
   }

-  protected void setRequestHeaders(HttpServletRequest servletRequest,  
HttpRequest req) {
+  protected void setRequestHeaders(HttpServletRequest servletRequest,  
HttpRequest req)
+        throws GadgetException {
     String xff  = servletRequest.getHeader("X-Forwarded-For");
     String remoteAddr = servletRequest.getRemoteAddr();
     if (!StringUtils.isEmpty(remoteAddr)) {