Remove keep-alive impulse IPCs from NaCl modules.

ppapi/shared_impl/ppapi_globals.cc

Index: ppapi/shared_impl/ppapi_globals.cc
diff --git a/ppapi/shared_impl/ppapi_globals.cc b/ppapi/shared_impl/ppapi_globals.cc
index 1d6d78f4f8c6e9132964ae7aecf0f103a4129cd8..5a93ad61d63699803468c738cc43c4d0a64f79f9 100644
--- a/ppapi/shared_impl/ppapi_globals.cc
+++ b/ppapi/shared_impl/ppapi_globals.cc
@@ -66,8 +66,6 @@ bool PpapiGlobals::IsHostGlobals() const { return false; }
 
 bool PpapiGlobals::IsPluginGlobals() const { return false; }
 
-void PpapiGlobals::MarkPluginIsActive() {}
-
 // static
 PpapiGlobals* PpapiGlobals::GetThreadLocalPointer() {
   return tls_ppapi_globals_for_test.Pointer()->Get();