Remove references to MessageLoopForIO in /remoting

MessageLoopForIO is going away soon. Use SingleThreadTaskExecutor
instead.

This CL was uploaded by git cl split.

R=lambroslambrou@chromium.org

Bug: 891670
Change-Id: Id1c49577b98d4adc705d1eec6a164382fb5aba77
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1731848
Auto-Submit: Carlos Caballero <carlscab@google.com>
Commit-Queue: Lambros Lambrou <lambroslambrou@chromium.org>
Reviewed-by: Lambros Lambrou <lambroslambrou@chromium.org>
Cr-Commit-Position: refs/heads/master@{#683676}

remoting/test/chromoting_test_driver_environment.cc

@@ -9,10 +9,11 @@
 
 #include "base/bind.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop.h"
 #include "base/message_loop/message_loop_current.h"
+#include "base/message_loop/message_pump_type.h"
 #include "base/run_loop.h"
 #include "base/strings/stringprintf.h"
+#include "base/task/single_thread_task_executor.h"
 #include "remoting/test/access_token_fetcher.h"
 #include "remoting/test/host_list_fetcher.h"
 #include "remoting/test/test_token_storage.h"
@@ -49,7 +50,8 @@ bool ChromotingTestDriverEnvironment::Initialize(
   }
 
   if (!base::MessageLoopCurrent::Get()) {
-    message_loop_.reset(new base::MessageLoopForIO);
+    executor_ = std::make_unique<base::SingleThreadTaskExecutor>(
+        base::MessagePumpType::IO);
   }
 
   // If a unit test has set |test_test_token_storage_| then we should use it
@@ -199,7 +201,7 @@ void ChromotingTestDriverEnvironment::TearDown() {
   // registered AtExitManager. The AtExitManager is torn down before the test
   // destructor is executed, so we tear down the MessageLoop here, while it is
   // still valid.
-  message_loop_.reset();
+  executor_.reset();
 }
 
 bool ChromotingTestDriverEnvironment::RetrieveAccessToken(

remoting/test/chromoting_test_driver_environment.h

@@ -16,7 +16,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
-class MessageLoopForIO;
+class SingleThreadTaskExecutor;
 }
 
 namespace remoting {
@@ -147,7 +147,7 @@ class ChromotingTestDriverEnvironment : public testing::Environment {
   remoting::test::HostListFetcher* test_host_list_fetcher_ = nullptr;
 
   // Used for running network request tasks.
-  std::unique_ptr<base::MessageLoopForIO> message_loop_;
+  std::unique_ptr<base::SingleThreadTaskExecutor> executor_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromotingTestDriverEnvironment);
 };