Extend IRT with nacl_irt_resource_open interface

src/shared/ppapi_proxy/ppruntime.h

Index: src/shared/ppapi_proxy/ppruntime.h
===================================================================
--- src/shared/ppapi_proxy/ppruntime.h	(revision 6419)
+++ src/shared/ppapi_proxy/ppruntime.h	(working copy)
@@ -10,6 +10,11 @@
 
 EXTERN_C_BEGIN
 
+// Initialize srpc connection to the browser. Some APIs like manifest file
+// opening do not need full ppapi initialization and so can be used after
+// this function returns.
+int IrtInit();
+
 // The entry point for the main thread of the PPAPI plugin process.
 int PpapiPluginMain();