[remoting android] Add and build host code.

remoting/host/me2me_desktop_environment.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "remoting/host/me2me_desktop_environment.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 69 matching lines @@
                                    client_session_control);
     bool active = curtain_->Activate();
     if (!active)
       LOG(ERROR) << "Failed to activate the curtain mode.";
     return active;
   }
 
   // Otherwise, if the session is shared with the local user start monitoring
   // the local input and create the in-session UI.
 
-#if defined(OS_LINUX)
+#if defined(OS_LINUX) || defined(OS_ANDROID)

[Sergey Ulanov, 2016/04/07 00:56:14]

I think this should default to true. We can disable host UI on linux only
because me2me is always "curtained" there, which I assume won't be the case on
Android.

[Lambros, 2016/04/12 21:58:04]

Done.

   bool want_user_interface = false;
 #elif defined(OS_MACOSX)
   // Don't try to display any UI on top of the system's login screen as this
   // is rejected by the Window Server on OS X 10.7.4, and prevents the
   // capturer from working (http://crbug.com/140984).
 
   // TODO(lambroslambrou): Use a better technique of detecting whether we're
   // running in the LoginWindow context, and refactor this into a separate
   // function to be used here and in CurtainMode::ActivateCurtain().
   bool want_user_interface = getuid() != 0;
@@ skipping 47 matching lines @@
   return std::move(desktop_environment);
 }
 
 void Me2MeDesktopEnvironmentFactory::SetEnableCurtaining(bool enable) {
   DCHECK(caller_task_runner()->BelongsToCurrentThread());
 
   curtain_enabled_ = enable;
 }
 
 }  // namespace remoting