Linux sandbox: change the return type of HandleRequest

sandbox/linux/syscall_broker/broker_process_unittest.cc

Index: sandbox/linux/syscall_broker/broker_process_unittest.cc
diff --git a/sandbox/linux/syscall_broker/broker_process_unittest.cc b/sandbox/linux/syscall_broker/broker_process_unittest.cc
index e7d5442c3b1ac656096ed6465258a2c1bd886f64..16a64656d268482d2d36f5bf4947d41abb4be4e4 100644
--- a/sandbox/linux/syscall_broker/broker_process_unittest.cc
+++ b/sandbox/linux/syscall_broker/broker_process_unittest.cc
@@ -31,6 +31,8 @@
 
 namespace sandbox {
 
+namespace syscall_broker {
+
 class BrokerProcessTestHelper {
  public:
   static int get_ipc_socketpair(const BrokerProcess* broker) {
@@ -472,4 +474,6 @@ SANDBOX_TEST_ALLOW_NOISE(BrokerProcess, RecvMsgDescriptorLeak) {
   SANDBOX_ASSERT(0 == IGNORE_EINTR(close(fd)));
 }
 
+}  // namespace syscall_broker
+
 }  // namespace sandbox