Remove video_channel() from Session interface

remoting/protocol/connection_to_client_unittest.cc

Index: remoting/protocol/connection_to_client_unittest.cc
diff --git a/remoting/protocol/connection_to_client_unittest.cc b/remoting/protocol/connection_to_client_unittest.cc
index 360951131e9e5ca683f61bcea988b44629e13d8e..8a8e1e8fa8a2d35e13a1225027c1bd551e641f2b 100644
--- a/remoting/protocol/connection_to_client_unittest.cc
+++ b/remoting/protocol/connection_to_client_unittest.cc
@@ -4,6 +4,7 @@
 
 #include "base/message_loop.h"
 #include "remoting/base/base_mock_objects.h"
+#include "remoting/base/constants.h"
 #include "remoting/protocol/fake_session.h"
 #include "remoting/protocol/connection_to_client.h"
 #include "remoting/protocol/protocol_mock_objects.h"
@@ -60,7 +61,9 @@ TEST_F(ConnectionToClientTest, SendUpdateStream) {
 
   // Verify that something has been written.
   // TODO(sergeyu): Verify that the correct data has been written.
-  EXPECT_GT(session_->video_channel()->written_data().size(), 0u);
+  ASSERT_TRUE(session_->GetStreamChannel(kVideoChannelName));
+  EXPECT_GT(session_->GetStreamChannel(kVideoChannelName)->
+            written_data().size(), 0u);
 
   // And then close the connection to ConnectionToClient.
   viewer_->Disconnect();