Add a way to implement GetInterface in the broker.

ppapi/cpp/module_embedder.h

Index: ppapi/cpp/module_embedder.h
diff --git a/ppapi/cpp/module_embedder.h b/ppapi/cpp/module_embedder.h
index b7b7d438a291198c8ea9287069209d258449d5e8..a1d00a864f39c883fc81dadb5b1598977873aae3 100644
--- a/ppapi/cpp/module_embedder.h
+++ b/ppapi/cpp/module_embedder.h
@@ -5,6 +5,8 @@
 #ifndef PPAPI_CPP_MODULE_EMBEDDER_H_
 #define PPAPI_CPP_MODULE_EMBEDDER_H_
 
+#include "ppapi/c/ppp.h"
+
 /// @file
 /// This file defines the APIs for creating a Module object.
 namespace pp {
@@ -20,6 +22,19 @@ class Module;
 /// failure. Upon failure, the module will be unloaded.
 pp::Module* CreateModule();
 
+/// Sets the get interface function in the broker process.
+///
+/// This function is only relevant when you're using the PPB_Broker interface
+/// in a trusted native plugin. In this case, you may need to implement
+/// PPP_GetInterface when the plugin is loaded in the unsandboxed process.
+/// Normally the C++ wrappers implement PPP_GetInterface for you but this
+/// doesn't work in the context of the broker process.
+//
+/// So if you need to implement PPP_* interfaces in the broker process, call
+/// this function in your PPP_InitializeBroker implementation which will set
+/// up the given function as implementing PPP_GetInterface.
+void SetBrokerGetInterfaceFunc(PP_GetInterface_Func broker_get_interface);
+
 }  // namespace pp
 
 #endif  // PPAPI_CPP_MODULE_EMBEDDER_H_