Clean up public interface of AttachmentBrokerUnprivileged.

ipc/attachment_broker_privileged.cc

Index: ipc/attachment_broker_privileged.cc
diff --git a/ipc/attachment_broker_privileged.cc b/ipc/attachment_broker_privileged.cc
index 85c1ac949cd858704effd0cb8dba4b4cb6ffefaf..900679862937a8abf00e12458c45ce46a5d21061 100644
--- a/ipc/attachment_broker_privileged.cc
+++ b/ipc/attachment_broker_privileged.cc
@@ -67,9 +67,7 @@ scoped_ptr<AttachmentBrokerPrivileged> CreateBroker() {
 // the global broker.
 class AttachmentBrokerMakeOnce {
  public:
-  AttachmentBrokerMakeOnce() {
-    attachment_broker_.reset(CreateBroker().release());
-  }
+  AttachmentBrokerMakeOnce() : attachment_broker_(CreateBroker()) {}
 
  private:
   scoped_ptr<IPC::AttachmentBrokerPrivileged> attachment_broker_;
@@ -128,6 +126,10 @@ void AttachmentBrokerPrivileged::DeregisterCommunicationChannel(
     endpoints_.erase(it);
 }
 
+bool AttachmentBrokerPrivileged::IsPrivilegedBroker() {
+  return true;
+}
+
 Sender* AttachmentBrokerPrivileged::GetSenderWithProcessId(base::ProcessId id) {
   get_lock()->AssertAcquired();
   auto it = std::find_if(endpoints_.begin(), endpoints_.end(),