Add IsScalingDisabled and PP_PRINTOUTPUTFORMAT_EMF to pepper printing interface.

ppapi/native_client/src/shared/ppapi_proxy/ppp_printing.srpc

 # Copyright (c) 2011 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # RPC methods used to implement PPP_Printing calls to the plugin.
 # See ppapi/c/dev/ppp_printing_dev.h for interface details.
 {
  'name': 'PppPrintingRpc',
  'rpcs': [
           {'name': 'PPP_Printing_QuerySupportedFormats',
@@ skipping 16 matching lines @@
                      ],
            'outputs': [['image_data', 'PP_Resource'],
                       ]
           },
           {'name': 'PPP_Printing_End',
            'inputs': [['instance', 'PP_Instance'],
                      ],
            'outputs': [
                       ]
           },
+          {'name': 'PPP_Printing_IsScalingDisabled',
+           'inputs': [['instance', 'PP_Instance'],
+                     ],
+           'outputs': [['result', 'int32_t'],  # PP_Bool
+                      ]
+          },
          ]
 }