Change Chromoting logger to be setup in plugin's NP_Initialize.

remoting/host/plugin/host_plugin.cc

Index: remoting/host/plugin/host_plugin.cc
diff --git a/remoting/host/plugin/host_plugin.cc b/remoting/host/plugin/host_plugin.cc
index f901a03db816b0f117c9a2c183b97c9130a5d48f..62d35c45cee2464b6b0f0c74d98d9e2aba732201 100644
--- a/remoting/host/plugin/host_plugin.cc
+++ b/remoting/host/plugin/host_plugin.cc
@@ -421,6 +421,9 @@ EXPORT NPError API_CALL NP_Initialize(NPNetscapeFuncs* npnetscape_funcs
   if(((npnetscape_funcs->version & 0xff00) >> 8) > NP_VERSION_MAJOR)
     return NPERR_INCOMPATIBLE_VERSION_ERROR;
 
+  // Register a global log handler.
+  HostNPScriptObject::RegisterLogger();
+
   g_at_exit_manager = new base::AtExitManager;
   g_npnetscape_funcs = npnetscape_funcs;
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
@@ -433,6 +436,10 @@ EXPORT NPError API_CALL NP_Shutdown() {
   VLOG(2) << "NP_Shutdown";
   delete g_at_exit_manager;
   g_at_exit_manager = NULL;
+
+  // Remove the global log handler.
+  HostNPScriptObject::UnregisterLogger();
+
   return NPERR_NO_ERROR;
 }