Add IsScalingDisabled and PP_PRINTOUTPUTFORMAT_EMF to pepper printing interface.

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

Index: ppapi/native_client/src/shared/ppapi_proxy/ppp_printing.srpc
diff --git a/ppapi/native_client/src/shared/ppapi_proxy/ppp_printing.srpc b/ppapi/native_client/src/shared/ppapi_proxy/ppp_printing.srpc
index c1301ef59748065969c3908619315fb2959a170b..608b9334dc51b97d9d4f673f865a85bcd30e1fab 100644
--- a/ppapi/native_client/src/shared/ppapi_proxy/ppp_printing.srpc
+++ b/ppapi/native_client/src/shared/ppapi_proxy/ppp_printing.srpc
@@ -34,5 +34,11 @@
            'outputs': [
                       ]
           },
+          {'name': 'PPP_Printing_IsScalingDisabled',
+           'inputs': [['instance', 'PP_Instance'],
+                     ],
+           'outputs': [['result', 'int32_t'],  # PP_Bool
+                      ]
+          },
          ]
 }