Add gpu targets to untrusted NaCl build.

ppapi/ppapi_proxy.gypi

Index: ppapi/ppapi_proxy.gypi
===================================================================
--- ppapi/ppapi_proxy.gypi	(revision 147791)
+++ ppapi/ppapi_proxy.gypi	(working copy)
@@ -145,7 +145,6 @@
           'proxy/proxy_array_output.h',
           'proxy/proxy_channel.cc',
           'proxy/proxy_channel.h',
-          'proxy/proxy_completion_callback_factory.h',
           'proxy/proxy_module.cc',
           'proxy/proxy_module.h',
           'proxy/proxy_object_var.cc',
@@ -172,7 +171,6 @@
           ['>(nacl_untrusted_build)==1', {
             'sources!': [
               'proxy/broker_dispatcher.cc',
-              'proxy/ppapi_command_buffer_proxy.cc',
               'proxy/ppb_audio_input_proxy.cc',
               'proxy/ppb_broker_proxy.cc',
               'proxy/ppb_buffer_proxy.cc',
@@ -181,7 +179,6 @@
               'proxy/ppb_flash_proxy.cc',
               'proxy/ppb_flash_menu_proxy.cc',
               'proxy/ppb_flash_message_loop_proxy.cc',
-              'proxy/ppb_graphics_3d_proxy.cc',
               'proxy/ppb_host_resolver_private_proxy.cc',
               'proxy/ppb_network_monitor_private_proxy.cc',
               'proxy/ppb_pdf_proxy.cc',
@@ -193,7 +190,6 @@
               'proxy/ppb_video_capture_proxy.cc',
               'proxy/ppb_video_decoder_proxy.cc',
               'proxy/ppb_x509_certificate_private_proxy.cc',
-              'proxy/ppp_graphics_3d_proxy.cc',
               'proxy/ppp_instance_private_proxy.cc',
               'proxy/ppp_video_decoder_proxy.cc',
               'proxy/serialized_flash_menu.cc',