Log a deprecation message when mobileSource is called with the JSON

type, asking users to use XML type instead.

lib/server/controller.js

@@ -14,6 +14,7 @@ var status = require('./status.js')
   , respondSuccess = responses.respondSuccess
   , checkMissingParams = responses.checkMissingParams
   , notYetImplemented = responses.notYetImplemented
+  , logDeprecationWarning = require('../helpers.js').logDeprecationWarning
   , _ = require('underscore');
 
 
@@ -370,6 +371,7 @@ exports.mobileSource = function (req, res) {
   var type = req.body.type;
 
   if (checkMissingParams(res, {type: type})) {
+    logDeprecationWarning('parameter', 'type');
     if (type.toLowerCase() === "xml") {
       req.device.getPageSourceXML(getResponseHandler(req, res));
     } else {
@@ -645,6 +647,8 @@ exports.elementSelected = function (req, res) {
 };
 
 exports.getPageSource = function (req, res) {
+  logger.warn("This method will change to return XML in a future version " +
+              "of Appium.");
   req.device.getPageSource(getResponseHandler(req, res));
 };