Linux sandbox: change the return type of HandleRequest

sandbox/linux/syscall_broker/broker_host.h

Index: sandbox/linux/syscall_broker/broker_host.h
diff --git a/sandbox/linux/syscall_broker/broker_host.h b/sandbox/linux/syscall_broker/broker_host.h
index 04c20ed5a1b8615a7c90c9f0c7ae0837babbdb33..c6612791cf77626b11f3ae6eb3bc2ce976b6c6d5 100644
--- a/sandbox/linux/syscall_broker/broker_host.h
+++ b/sandbox/linux/syscall_broker/broker_host.h
@@ -18,10 +18,12 @@ class BrokerPolicy;
 // |ipc_channel| according to |broker_policy|.
 class BrokerHost {
  public:
+  enum class RequestStatus { LOST_CLIENT = 0, SUCCESS, FAILURE };
+
   BrokerHost(const BrokerPolicy& broker_policy, int ipc_channel);
   ~BrokerHost();
 
-  bool HandleRequest() const;
+  RequestStatus HandleRequest() const;
 
  private:
   const BrokerPolicy& broker_policy_;