Pepper: Add a X-Requested-With header to URL requests done for Pepper plugins.

webkit/glue/weburlrequest_extradata_impl.h

Index: webkit/glue/weburlrequest_extradata_impl.h
diff --git a/webkit/glue/weburlrequest_extradata_impl.h b/webkit/glue/weburlrequest_extradata_impl.h
index d4b2c194b6c14d3448ddbb79cb69f82ffcf43324..c7bbe6934b799aa10ad3bbd54db224b07e0a5cbf 100644
--- a/webkit/glue/weburlrequest_extradata_impl.h
+++ b/webkit/glue/weburlrequest_extradata_impl.h
@@ -21,21 +21,25 @@ class WEBKIT_GLUE_EXPORT WebURLRequestExtraDataImpl :
   // |custom_user_agent| is used to communicate an overriding custom user agent
   // to |RenderViewImpl::willSendRequest()|; set to a null string to indicate no
   // override and an empty string to indicate that there should be no user
-  // agent. This needs to be here, instead of content's |RequestExtraData| since
-  // ppb_url_request_info_impl.cc needs to be able to set it.
+  // agent. |requested_with| is used to set a X-Requested-With header for
+  // requests done on behalf of plugins. These need to be here, instead of
+  // content's |RequestExtraData| since they're set from webkit/plugins/ppapi.
   explicit WebURLRequestExtraDataImpl(
       WebKit::WebReferrerPolicy referrer_policy,
-      const WebKit::WebString& custom_user_agent);
+      const WebKit::WebString& custom_user_agent,
+      const WebKit::WebString& requested_with);
   virtual ~WebURLRequestExtraDataImpl();
 
   WebKit::WebReferrerPolicy referrer_policy() const { return referrer_policy_; }
   const WebKit::WebString& custom_user_agent() const {
     return custom_user_agent_;
   }
+  const WebKit::WebString& requested_with() const { return requested_with_; }
 
  private:
   WebKit::WebReferrerPolicy referrer_policy_;
   WebKit::WebString custom_user_agent_;
+  WebKit::WebString requested_with_;
 
   DISALLOW_COPY_AND_ASSIGN(WebURLRequestExtraDataImpl);
 };