Ensure that PP_Instance values are unique within a plugin process in addition...

ppapi/ppapi_shared_proxy.gypi

 # Copyright (c) 2010 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   'targets': [
     {
       'target_name': 'ppapi_shared_impl',
       'type': 'static_library',
       'dependencies': [
@@ skipping 40 matching lines @@
         'proxy/dispatcher.h',
         'proxy/host_dispatcher.cc',
         'proxy/host_dispatcher.h',
         'proxy/host_resource.h',
         'proxy/host_var_serialization_rules.cc',
         'proxy/host_var_serialization_rules.h',
         'proxy/interface_proxy.cc',
         'proxy/interface_proxy.h',
         'proxy/plugin_dispatcher.cc',
         'proxy/plugin_dispatcher.h',
+        'proxy/plugin_message_filter.cc',
+        'proxy/plugin_message_filter.h',
         'proxy/plugin_resource.cc',
         'proxy/plugin_resource.h',
         'proxy/plugin_resource_tracker.cc',
         'proxy/plugin_resource_tracker.h',
         'proxy/plugin_var_serialization_rules.cc',
         'proxy/plugin_var_serialization_rules.h',
         'proxy/plugin_var_tracker.cc',
         'proxy/plugin_var_tracker.h',
         'proxy/ppapi_messages.cc',
         'proxy/ppapi_messages.h',
@@ skipping 74 matching lines @@
         ['OS=="win"', {
         }],
         ['OS=="linux"', {
         }],
         ['OS=="mac"', {
         }]
       ],
     },
   ],
 }