Use ScopedRefNPObject to pass NPObjects in the host plugin.

remoting/host/plugin/host_plugin_utils.cc

Index: remoting/host/plugin/host_plugin_utils.cc
diff --git a/remoting/host/plugin/host_plugin_utils.cc b/remoting/host/plugin/host_plugin_utils.cc
index c1682c4b8f1425986dfbf00ab07a5926927f8c0e..bb5d2f3d5007a3a391a8bef8d241f534a6ba9710 100644
--- a/remoting/host/plugin/host_plugin_utils.cc
+++ b/remoting/host/plugin/host_plugin_utils.cc
@@ -47,6 +47,11 @@ ScopedRefNPObject::ScopedRefNPObject(NPObject* object)
   *this = object;
 }
 
+ScopedRefNPObject::ScopedRefNPObject(const ScopedRefNPObject& object)
+    : object_(NULL) {
+  *this = object;
+}
+
 ScopedRefNPObject::~ScopedRefNPObject() {
   *this = NULL;
 }
@@ -62,4 +67,9 @@ ScopedRefNPObject& ScopedRefNPObject::operator=(NPObject* object) {
   return *this;
 }
 
+ScopedRefNPObject& ScopedRefNPObject::operator=(
+    const ScopedRefNPObject& object) {
+  return *this = object.get();
+}
+
 }  // namespace remoting