Remove references to MessageLoopForIO in /net

MessageLoopForIO is going away soon. Use SingleThreadTaskExecutor
instead.

This CL was uploaded by git cl split.

R=nharper@chromium.org

Bug: 891670
Change-Id: Ife2524ad96a7a7c3c7df99d996f6d101a3afa88b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1733587
Auto-Submit: Carlos Caballero <carlscab@google.com>
Commit-Queue: Nick Harper <nharper@chromium.org>
Reviewed-by: Nick Harper <nharper@chromium.org>
Cr-Commit-Position: refs/heads/master@{#683690}

net/test/embedded_test_server/embedded_test_server_unittest.cc

@@ -11,13 +11,13 @@
 #include "base/bind_helpers.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
-#include "base/message_loop/message_loop.h"
 #include "base/message_loop/message_pump_type.h"
 #include "base/path_service.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/synchronization/lock.h"
+#include "base/task/single_thread_task_executor.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "net/base/test_completion_callback.h"
@@ -525,9 +525,11 @@ class EmbeddedTestServerThreadingTestDelegate
 
   // base::PlatformThread::Delegate:
   void ThreadMain() override {
-    std::unique_ptr<base::MessageLoop> loop;
-    if (message_loop_present_on_initialize_)
-      loop = std::make_unique<base::MessageLoopForIO>();
+    std::unique_ptr<base::SingleThreadTaskExecutor> executor;
+    if (message_loop_present_on_initialize_) {
+      executor = std::make_unique<base::SingleThreadTaskExecutor>(
+          base::MessagePumpType::IO);
+    }
 
     // Create the test server instance.
     EmbeddedTestServer server(type_);
@@ -536,14 +538,17 @@ class EmbeddedTestServerThreadingTestDelegate
     ASSERT_TRUE(server.Start());
 
     // Make a request and wait for the reply.
-    if (!loop)
-      loop = std::make_unique<base::MessageLoopForIO>();
+    if (!executor) {
+      executor = std::make_unique<base::SingleThreadTaskExecutor>(
+          base::MessagePumpType::IO);
+    }
 
     std::unique_ptr<URLFetcher> fetcher =
         URLFetcher::Create(server.GetURL("/test?q=foo"), URLFetcher::GET, this,
                            TRAFFIC_ANNOTATION_FOR_TESTS);
     auto test_context_getter =
-        base::MakeRefCounted<TestURLRequestContextGetter>(loop->task_runner());
+        base::MakeRefCounted<TestURLRequestContextGetter>(
+            executor->task_runner());
     fetcher->SetRequestContext(test_context_getter.get());
     base::RunLoop run_loop;
     quit_run_loop_ = run_loop.QuitClosure();
@@ -553,7 +558,7 @@ class EmbeddedTestServerThreadingTestDelegate
 
     // Shut down.
     if (message_loop_present_on_shutdown_)
-      loop.reset();
+      executor.reset();
 
     ASSERT_TRUE(server.ShutdownAndWaitUntilComplete());
   }

net/tools/disk_cache_memory_test/disk_cache_memory_test.cc

@@ -15,13 +15,14 @@
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop.h"
+#include "base/message_loop/message_pump_type.h"
 #include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_piece.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
+#include "base/task/single_thread_task_executor.h"
 #include "base/task/thread_pool/thread_pool.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "net/base/cache_type.h"
@@ -258,7 +259,7 @@ bool ParseAndStoreSpec(const std::string& spec_str,
 
 bool Main(int argc, char** argv) {
   base::AtExitManager at_exit_manager;
-  base::MessageLoopForIO message_loop;
+  base::SingleThreadTaskExecutor executor(base::MessagePumpType::IO);
   base::ThreadPoolInstance::CreateAndStartWithDefaultParams(
       "disk_cache_memory_test");
   base::CommandLine::Init(argc, argv);