Add an IPC channel between the NaCl loader process and the renderer.

ppapi/native_client/src/trusted/plugin/module_ppapi.cc

Index: ppapi/native_client/src/trusted/plugin/module_ppapi.cc
===================================================================
--- ppapi/native_client/src/trusted/plugin/module_ppapi.cc	(revision 143163)
+++ ppapi/native_client/src/trusted/plugin/module_ppapi.cc	(working copy)
@@ -13,6 +13,8 @@
 #include "ppapi/c/private/ppb_nacl_private.h"
 #include "ppapi/cpp/module.h"
 
+StartPpapiProxyFunc start_ppapi_proxy;
+
 namespace plugin {
 
 class ModulePpapi : public pp::Module {
@@ -47,6 +49,9 @@
     launch_nacl_process = reinterpret_cast<LaunchNaClProcessFunc>(
         private_interface_->LaunchSelLdr);
 
+    start_ppapi_proxy = reinterpret_cast<StartPpapiProxyFunc>(
+        private_interface_->StartPpapiProxy);
+
 #if NACL_LINUX || NACL_OSX
     // Note that currently we do not need random numbers inside the
     // NaCl trusted plugin on Unix, but NaClSecureRngModuleInit() is