[Chromoting] Use HostExperimentSessionPlugin in host

remoting/host/host_session_options_unittest.cc

Index: remoting/host/host_session_options_unittest.cc
diff --git a/remoting/host/host_session_options_unittest.cc b/remoting/host/host_session_options_unittest.cc
index f994934417bf983a7d800d25f91ad89607dbc2ed..1c7195bc5f67aea189e9b3db20ba6e8624bec5e2 100644
--- a/remoting/host/host_session_options_unittest.cc
+++ b/remoting/host/host_session_options_unittest.cc
@@ -7,7 +7,6 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace remoting {
-namespace protocol {
 
 TEST(HostSessionOptionsTest, ShouldBeAbleToAppendOptions) {
   HostSessionOptions options;
@@ -52,5 +51,4 @@ TEST(HostSessionOptionsTest, ImportAndExport) {
   ASSERT_EQ(options.Export(), other.Export());
 }
 
-}  // namespace protocol
 }  // namespace remoting