chrome: Remove use of MessageLoopProxy and deprecated MessageLoop APIs

This patch was mostly autogenerated with https://codereview.chromium.org/1010073002/.

BUG=465354

Review URL: https://codereview.chromium.org/1167163002

Cr-Commit-Position: refs/heads/master@{#333745}

71 files changed, 462 insertions, 458 deletions

diff --git a/chrome/app_shim/chrome_main_app_mode_mac.mm b/chrome/app_shim/chrome_main_app_mode_mac.mm
index ca3d271..98630a6 100644
--- a/chrome/app_shim/chrome_main_app_mode_mac.mm
+++ b/chrome/app_shim/chrome_main_app_mode_mac.mm
@@ -211,10 +211,8 @@ void AppShimController::Init() {
 void AppShimController::CreateChannelAndSendLaunchApp(
     const base::FilePath& socket_path) {
   IPC::ChannelHandle handle(socket_path.value());
-  channel_ = IPC::ChannelProxy::Create(handle,
-                                       IPC::Channel::MODE_NAMED_CLIENT,
-                                       this,
-                                       g_io_thread->message_loop_proxy().get());
+  channel_ = IPC::ChannelProxy::Create(handle, IPC::Channel::MODE_NAMED_CLIENT,
+                                       this, g_io_thread->task_runner().get());
 
   bool launched_by_chrome = base::CommandLine::ForCurrentProcess()->HasSwitch(
       app_mode::kLaunchedByChromeProcessId);
diff --git a/chrome/common/local_discovery/local_domain_resolver_unittest.cc b/chrome/common/local_discovery/local_domain_resolver_unittest.cc
index 2a61283..f55783e 100644
--- a/chrome/common/local_discovery/local_domain_resolver_unittest.cc
+++ b/chrome/common/local_discovery/local_domain_resolver_unittest.cc
@@ -2,6 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/local_discovery/service_discovery_client_impl.h"
 #include "net/dns/mdns_client_impl.h"
 #include "net/dns/mock_mdns_socket_factory.h"
@@ -81,7 +84,7 @@ class LocalDomainResolverTest : public testing::Test {
     base::CancelableCallback<void()> callback(base::Bind(
         &base::MessageLoop::Quit,
         base::Unretained(base::MessageLoop::current())));
-    base::MessageLoop::current()->PostDelayedTask(
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
         FROM_HERE, callback.callback(), time_period);
 
     base::MessageLoop::current()->Run();
diff --git a/chrome/common/local_discovery/service_discovery_client_impl.cc b/chrome/common/local_discovery/service_discovery_client_impl.cc
index c86f726..733e166 100644
--- a/chrome/common/local_discovery/service_discovery_client_impl.cc
+++ b/chrome/common/local_discovery/service_discovery_client_impl.cc
@@ -4,10 +4,12 @@
 
 #include <utility>
 
+#include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/singleton.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
 #include "base/stl_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/local_discovery/service_discovery_client_impl.h"
 #include "net/dns/dns_protocol.h"
 #include "net/dns/record_rdata.h"
@@ -270,10 +272,9 @@ void ServiceWatcherImpl::DeferUpdate(ServiceWatcher::UpdateType update_type,
 
   if (found != services_.end() && !found->second->update_pending()) {
     found->second->set_update_pending(true);
-    base::MessageLoop::current()->PostTask(
-        FROM_HERE,
-        base::Bind(&ServiceWatcherImpl::DeliverDeferredUpdate, AsWeakPtr(),
-                   update_type, service_name));
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(&ServiceWatcherImpl::DeliverDeferredUpdate,
+                              AsWeakPtr(), update_type, service_name));
   }
 }
 
@@ -326,12 +327,10 @@ void ServiceWatcherImpl::OnNsecRecord(const std::string& name,
 
 void ServiceWatcherImpl::ScheduleQuery(int timeout_seconds) {
   if (timeout_seconds <= kMaxRequeryTimeSeconds) {
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&ServiceWatcherImpl::SendQuery,
-                   AsWeakPtr(),
-                   timeout_seconds * 2 /*next_timeout_seconds*/,
-                   false /*force_update*/),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&ServiceWatcherImpl::SendQuery, AsWeakPtr(),
+                              timeout_seconds * 2 /*next_timeout_seconds*/,
+                              false /*force_update*/),
         base::TimeDelta::FromSeconds(timeout_seconds));
   }
 }
@@ -560,9 +559,8 @@ void LocalDomainResolverImpl::OnTransactionComplete(
         &LocalDomainResolverImpl::SendResolvedAddresses,
         base::Unretained(this)));
 
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        timeout_callback_.callback(),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, timeout_callback_.callback(),
         base::TimeDelta::FromMilliseconds(kLocalDomainSecondAddressTimeoutMs));
   } else if (transactions_finished_ == 2
       || address_family_ != net::ADDRESS_FAMILY_UNSPECIFIED) {
diff --git a/chrome/common/local_discovery/service_discovery_client_unittest.cc b/chrome/common/local_discovery/service_discovery_client_unittest.cc
index 878bca1..ed6db5c 100644
--- a/chrome/common/local_discovery/service_discovery_client_unittest.cc
+++ b/chrome/common/local_discovery/service_discovery_client_unittest.cc
@@ -2,8 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/location.h"
 #include "base/memory/weak_ptr.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/local_discovery/service_discovery_client_impl.h"
 #include "net/base/net_errors.h"
 #include "net/dns/dns_protocol.h"
@@ -213,7 +216,7 @@ class ServiceDiscoveryTest : public ::testing::Test {
   void RunFor(base::TimeDelta time_period) {
     base::CancelableCallback<void()> callback(base::Bind(
         &ServiceDiscoveryTest::Stop, base::Unretained(this)));
-    base::MessageLoop::current()->PostDelayedTask(
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
         FROM_HERE, callback.callback(), time_period);
 
     base::MessageLoop::current()->Run();
diff --git a/chrome/common/profiling.cc b/chrome/common/profiling.cc
index 07cc8de..6dc28c6 100644
--- a/chrome/common/profiling.cc
+++ b/chrome/common/profiling.cc
@@ -9,7 +9,8 @@
 #include "base/command_line.h"
 #include "base/debug/profiler.h"
 #include "base/lazy_instance.h"
-#include "base/message_loop/message_loop.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
 #include "base/threading/thread.h"
 #include "chrome/common/chrome_switches.h"
@@ -82,9 +83,8 @@ void FlushProfilingData(base::Thread* thread) {
       flush_seconds = kProfilingFlushSeconds;
     }
   }
-  thread->message_loop()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&FlushProfilingData, thread),
+  thread->task_runner()->PostDelayedTask(
+      FROM_HERE, base::Bind(&FlushProfilingData, thread),
       base::TimeDelta::FromSeconds(flush_seconds));
 }
 
@@ -99,8 +99,8 @@ class ProfilingThreadControl {
       return;
     thread_ = new base::Thread("Profiling_Flush");
     thread_->Start();
-    thread_->message_loop()->PostTask(
-        FROM_HERE, base::Bind(&FlushProfilingData, thread_));
+    thread_->task_runner()->PostTask(FROM_HERE,
+                                     base::Bind(&FlushProfilingData, thread_));
   }
 
   void Stop() {
diff --git a/chrome/common/service_process_util.h b/chrome/common/service_process_util.h
index 9067623..7783e76 100644
--- a/chrome/common/service_process_util.h
+++ b/chrome/common/service_process_util.h
@@ -26,7 +26,7 @@ class NSString;
 
 namespace base {
 class CommandLine;
-class MessageLoopProxy;
+class SingleThreadTaskRunner;
 }
 
 // Return the IPC channel to connect to the service process.
@@ -88,11 +88,10 @@ class ServiceProcessState {
   // This method is called when the service process is running and initialized.
   // |terminate_task| is invoked when we get a terminate request from another
   // process (in the same thread that called SignalReady). It can be NULL.
-  // |message_loop_proxy| must be of type IO and is the loop that POSIX uses
+  // |task_runner| must be of type IO and is the loop that POSIX uses
   // to monitor the service process.
-  bool SignalReady(
-      base::MessageLoopProxy* message_loop_proxy,
-      const base::Closure& terminate_task);
+  bool SignalReady(base::SingleThreadTaskRunner* task_runner,
+                   const base::Closure& terminate_task);
 
   // Signal that the service process is stopped.
   void SignalStopped();
diff --git a/chrome/common/service_process_util_posix.cc b/chrome/common/service_process_util_posix.cc
index 6a655ca..9ec327c 100644
--- a/chrome/common/service_process_util_posix.cc
+++ b/chrome/common/service_process_util_posix.cc
@@ -6,8 +6,9 @@
 
 #include "base/basictypes.h"
 #include "base/bind.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/location.h"
 #include "base/posix/eintr_wrapper.h"
+#include "base/single_thread_task_runner.h"
 #include "base/synchronization/waitable_event.h"
 #include "chrome/common/multi_process_lock.h"
 
@@ -161,9 +162,8 @@ void ServiceProcessState::CreateState() {
   state_->AddRef();
 }
 
-bool ServiceProcessState::SignalReady(
-    base::MessageLoopProxy* message_loop_proxy,
-    const base::Closure& terminate_task) {
+bool ServiceProcessState::SignalReady(base::SingleThreadTaskRunner* task_runner,
+                                      const base::Closure& terminate_task) {
   DCHECK(state_);
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
@@ -181,11 +181,9 @@ bool ServiceProcessState::SignalReady(
   base::WaitableEvent signal_ready(true, false);
   bool success = false;
 
-  message_loop_proxy->PostTask(FROM_HERE,
-      base::Bind(&ServiceProcessState::StateData::SignalReady,
-                 state_,
-                 &signal_ready,
-                 &success));
+  task_runner->PostTask(FROM_HERE,
+                        base::Bind(&ServiceProcessState::StateData::SignalReady,
+                                   state_, &signal_ready, &success));
   signal_ready.Wait();
   return success;
 }
diff --git a/chrome/common/service_process_util_unittest.cc b/chrome/common/service_process_util_unittest.cc
index 9e4ba36..1881924 100644
--- a/chrome/common/service_process_util_unittest.cc
+++ b/chrome/common/service_process_util_unittest.cc
@@ -8,8 +8,10 @@
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
+#include "base/location.h"
 #include "base/process/kill.h"
 #include "base/process/launch.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_split.h"
 
 #if !defined(OS_MACOSX)
@@ -52,7 +54,7 @@ void ShutdownTask(base::MessageLoop* loop) {
   // Quit the main message loop.
   ASSERT_FALSE(g_good_shutdown);
   g_good_shutdown = true;
-  loop->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+  loop->task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
 }
 
 }  // namespace
@@ -70,8 +72,8 @@ class ServiceProcessStateTest : public base::MultiProcessTest {
   ServiceProcessStateTest();
   ~ServiceProcessStateTest() override;
   void SetUp() override;
-  base::MessageLoopProxy* IOMessageLoopProxy() {
-    return io_thread_.message_loop_proxy().get();
+  base::SingleThreadTaskRunner* IOMessageLoopProxy() {
+    return io_thread_.task_runner().get();
   }
   void LaunchAndWait(const std::string& name);
 
@@ -228,11 +230,11 @@ MULTIPROCESS_TEST_MAIN(ServiceProcessStateTestShutdown) {
   ServiceProcessState state;
   EXPECT_TRUE(state.Initialize());
   EXPECT_TRUE(state.SignalReady(
-      io_thread_.message_loop_proxy().get(),
+      io_thread_.task_runner().get(),
       base::Bind(&ShutdownTask, base::MessageLoop::current())));
-  message_loop.PostDelayedTask(FROM_HERE,
-                               base::MessageLoop::QuitClosure(),
-                               TestTimeouts::action_max_timeout());
+  message_loop.task_runner()->PostDelayedTask(
+      FROM_HERE, base::MessageLoop::QuitClosure(),
+      TestTimeouts::action_max_timeout());
   EXPECT_FALSE(g_good_shutdown);
   message_loop.Run();
   EXPECT_TRUE(g_good_shutdown);
@@ -274,7 +276,7 @@ class ServiceProcessStateFileManipulationTest : public ::testing::Test {
         new Launchd::ScopedInstance(mock_launchd_.get()));
     ASSERT_TRUE(service_process_state_.Initialize());
     ASSERT_TRUE(service_process_state_.SignalReady(
-        io_thread_.message_loop_proxy().get(), base::Closure()));
+        io_thread_.task_runner().get(), base::Closure()));
     loop_.PostDelayedTask(FROM_HERE,
                           base::MessageLoop::QuitClosure(),
                           TestTimeouts::action_max_timeout());
@@ -285,8 +287,8 @@ class ServiceProcessStateFileManipulationTest : public ::testing::Test {
   const base::FilePath& bundle_path() const { return bundle_path_; }
   const base::FilePath& GetTempDirPath() const { return temp_dir_.path(); }
 
-  base::MessageLoopProxy* GetIOMessageLoopProxy() {
-    return io_thread_.message_loop_proxy().get();
+  base::SingleThreadTaskRunner* GetIOMessageLoopProxy() {
+    return io_thread_.task_runner().get();
   }
   void Run() { loop_.Run(); }
 
diff --git a/chrome/common/service_process_util_win.cc b/chrome/common/service_process_util_win.cc
index 6aac388..df7c039 100644
--- a/chrome/common/service_process_util_win.cc
+++ b/chrome/common/service_process_util_win.cc
@@ -132,9 +132,8 @@ bool ServiceProcessState::TakeSingletonLock() {
   return true;
 }
 
-bool ServiceProcessState::SignalReady(
-    base::MessageLoopProxy* message_loop_proxy,
-    const base::Closure& terminate_task) {
+bool ServiceProcessState::SignalReady(base::SingleThreadTaskRunner* task_runner,
+                                      const base::Closure& terminate_task) {
   DCHECK(state_);
   DCHECK(state_->ready_event.IsValid());
   if (!SetEvent(state_->ready_event.Get())) {
diff --git a/chrome/common/worker_thread_ticker.cc b/chrome/common/worker_thread_ticker.cc
index 1fa75e9..8b78d97 100644
--- a/chrome/common/worker_thread_ticker.cc
+++ b/chrome/common/worker_thread_ticker.cc
@@ -8,8 +8,9 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/location.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/threading/thread.h"
 
 WorkerThreadTicker::WorkerThreadTicker(int tick_interval)
@@ -76,7 +77,7 @@ bool WorkerThreadTicker::Stop() {
 }
 
 void WorkerThreadTicker::ScheduleTimerTask() {
-  timer_thread_.message_loop()->PostDelayedTask(
+  timer_thread_.task_runner()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&WorkerThreadTicker::TimerTask, base::Unretained(this)),
       tick_interval_);
diff --git a/chrome/common/worker_thread_ticker_unittest.cc b/chrome/common/worker_thread_ticker_unittest.cc
index 4f7dc0d..dbb2e01 100644
--- a/chrome/common/worker_thread_ticker_unittest.cc
+++ b/chrome/common/worker_thread_ticker_unittest.cc
@@ -4,7 +4,10 @@
 
 #include "chrome/common/worker_thread_ticker.h"
 
+#include "base/location.h"
 #include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/threading/platform_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -18,7 +21,8 @@ class TestCallback : public WorkerThreadTicker::Callback {
     counter_++;
 
     // Finish the test faster.
-    message_loop_->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+    message_loop_->task_runner()->PostTask(FROM_HERE,
+                                           base::MessageLoop::QuitClosure());
   }
 
   int counter() const { return counter_; }
@@ -36,9 +40,8 @@ class LongCallback : public WorkerThreadTicker::Callback {
 };
 
 void RunMessageLoopForAWhile() {
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      base::MessageLoop::QuitClosure(),
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, base::MessageLoop::QuitClosure(),
       base::TimeDelta::FromMilliseconds(500));
   base::MessageLoop::current()->Run();
 }
diff --git a/chrome/renderer/chrome_content_renderer_client_browsertest.cc b/chrome/renderer/chrome_content_renderer_client_browsertest.cc
index 14b2526..f373539 100644
--- a/chrome/renderer/chrome_content_renderer_client_browsertest.cc
+++ b/chrome/renderer/chrome_content_renderer_client_browsertest.cc
@@ -9,6 +9,7 @@
 
 #include "base/command_line.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/grit/generated_resources.h"
@@ -53,7 +54,7 @@ TEST_F(InstantProcessNavigationTest, ForkForNavigationsToSearchURLs) {
   ChromeContentRendererClient* client =
       static_cast<ChromeContentRendererClient*>(content_renderer_client_.get());
   chrome_render_thread_->set_io_message_loop_proxy(
-      base::MessageLoopProxy::current());
+      base::ThreadTaskRunnerHandle::Get());
   client->RenderThreadStarted();
   std::vector<GURL> search_urls;
   search_urls.push_back(GURL("http://example.com/search"));
diff --git a/chrome/renderer/chrome_mock_render_thread.cc b/chrome/renderer/chrome_mock_render_thread.cc
index e197222..64d809e 100644
--- a/chrome/renderer/chrome_mock_render_thread.cc
+++ b/chrome/renderer/chrome_mock_render_thread.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/renderer/chrome_mock_render_thread.h"
 
+#include "base/single_thread_task_runner.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(ENABLE_EXTENSIONS)
@@ -18,12 +19,12 @@ ChromeMockRenderThread::~ChromeMockRenderThread() {
 
 scoped_refptr<base::SingleThreadTaskRunner>
 ChromeMockRenderThread::GetIOMessageLoopProxy() {
-  return io_message_loop_proxy_;
+  return io_task_runner_;
 }
 
 void ChromeMockRenderThread::set_io_message_loop_proxy(
-    const scoped_refptr<base::MessageLoopProxy>& proxy) {
-  io_message_loop_proxy_ = proxy;
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner) {
+  io_task_runner_ = task_runner;
 }
 
 bool ChromeMockRenderThread::OnMessageReceived(const IPC::Message& msg) {
diff --git a/chrome/renderer/chrome_mock_render_thread.h b/chrome/renderer/chrome_mock_render_thread.h
index f6e460f..f15d584 100644
--- a/chrome/renderer/chrome_mock_render_thread.h
+++ b/chrome/renderer/chrome_mock_render_thread.h
@@ -25,7 +25,7 @@ class ChromeMockRenderThread : public content::MockRenderThread {
 
   // Set IO message loop proxy.
   void set_io_message_loop_proxy(
-      const scoped_refptr<base::MessageLoopProxy>& proxy);
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
 
  private:
   // Overrides base class implementation to add custom handling for
@@ -41,7 +41,7 @@ class ChromeMockRenderThread : public content::MockRenderThread {
                                 int* port_id);
 #endif
 
-  scoped_refptr<base::MessageLoopProxy> io_message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeMockRenderThread);
 };
diff --git a/chrome/renderer/chrome_render_process_observer.cc b/chrome/renderer/chrome_render_process_observer.cc
index 3fcc1c4c..2d2edce 100644
--- a/chrome/renderer/chrome_render_process_observer.cc
+++ b/chrome/renderer/chrome_render_process_observer.cc
@@ -11,14 +11,16 @@
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_util.h"
+#include "base/location.h"
 #include "base/memory/weak_ptr.h"
-#include "base/message_loop/message_loop.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/native_library.h"
 #include "base/path_service.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/threading/platform_thread.h"
 #include "chrome/common/child_process_logging.h"
 #include "chrome/common/chrome_paths.h"
@@ -38,13 +40,13 @@
 #include "crypto/nss_util.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_module.h"
-#include "third_party/mojo/src/mojo/public/cpp/bindings/strong_binding.h"
 #include "third_party/WebKit/public/web/WebCache.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebFrame.h"
 #include "third_party/WebKit/public/web/WebRuntimeFeatures.h"
 #include "third_party/WebKit/public/web/WebSecurityPolicy.h"
 #include "third_party/WebKit/public/web/WebView.h"
+#include "third_party/mojo/src/mojo/public/cpp/bindings/strong_binding.h"
 
 #if defined(ENABLE_EXTENSIONS)
 #include "chrome/renderer/extensions/extension_localization_peer.h"
@@ -72,7 +74,7 @@ class RendererResourceDelegate : public content::ResourceDispatcherDelegate {
     // Update the browser about our cache.
     // Rate limit informing the host of our cache stats.
     if (!weak_factory_.HasWeakPtrs()) {
-      base::MessageLoop::current()->PostDelayedTask(
+      base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
           FROM_HERE,
           base::Bind(&RendererResourceDelegate::InformHostOfCacheStats,
                      weak_factory_.GetWeakPtr()),
@@ -168,12 +170,12 @@ class ResourceUsageReporterImpl : public ResourceUsageReporter {
     usage_data_->v8_bytes_used = heap_stats.used_heap_size();
     base::Closure collect = base::Bind(
         &ResourceUsageReporterImpl::CollectOnWorkerThread,
-        base::MessageLoopProxy::current(), weak_factory_.GetWeakPtr());
+        base::ThreadTaskRunnerHandle::Get(), weak_factory_.GetWeakPtr());
     workers_to_go_ = RenderThread::Get()->PostTaskToAllWebWorkers(collect);
     if (workers_to_go_) {
       // The guard task to send out partial stats
       // in case some workers are not responsive.
-      base::MessageLoopProxy::current()->PostDelayedTask(
+      base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
           FROM_HERE, base::Bind(&ResourceUsageReporterImpl::SendResults,
                                 weak_factory_.GetWeakPtr()),
           base::TimeDelta::FromMilliseconds(kWaitForWorkersStatsTimeoutMS));
diff --git a/chrome/renderer/extensions/cast_streaming_native_handler.cc b/chrome/renderer/extensions/cast_streaming_native_handler.cc
index 5275f2d..66fb8a7 100644
--- a/chrome/renderer/extensions/cast_streaming_native_handler.cc
+++ b/chrome/renderer/extensions/cast_streaming_native_handler.cc
@@ -7,9 +7,11 @@
 #include <functional>
 #include <iterator>
 
+#include "base/location.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/extensions/api/cast_streaming_receiver_session.h"
 #include "chrome/common/extensions/api/cast_streaming_rtp_stream.h"
 #include "chrome/common/extensions/api/cast_streaming_udp_transport.h"
@@ -259,14 +261,11 @@ void CastStreamingNativeHandler::CreateCastSession(
   // invalid context when the callback is invoked.
   create_callback_.Reset(isolate, args[2].As<v8::Function>());
 
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
-      base::Bind(
-          &CastStreamingNativeHandler::CallCreateCallback,
-          weak_factory_.GetWeakPtr(),
-          base::Passed(&stream1),
-          base::Passed(&stream2),
-          base::Passed(&udp_transport)));
+      base::Bind(&CastStreamingNativeHandler::CallCreateCallback,
+                 weak_factory_.GetWeakPtr(), base::Passed(&stream1),
+                 base::Passed(&stream2), base::Passed(&udp_transport)));
 }
 
 void CastStreamingNativeHandler::CallCreateCallback(
diff --git a/chrome/renderer/media/cast_receiver_session.cc b/chrome/renderer/media/cast_receiver_session.cc
index f374549..404fb03 100644
--- a/chrome/renderer/media/cast_receiver_session.cc
+++ b/chrome/renderer/media/cast_receiver_session.cc
@@ -4,7 +4,9 @@
 
 #include "chrome/renderer/media/cast_receiver_session.h"
 
+#include "base/location.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/renderer/media/cast_receiver_audio_valve.h"
 #include "content/public/renderer/render_thread.h"
 #include "media/base/audio_capturer_source.h"
@@ -92,9 +94,8 @@ void CastReceiverSession::Start(
       new CastReceiverSession::AudioCapturerSource(this));
   scoped_ptr<media::VideoCapturerSource> video(
       new CastReceiverSession::VideoCapturerSource(this));
-  base::MessageLoop::current()->PostTask(
-      FROM_HERE,
-      base::Bind(start_callback, audio, base::Passed(&video)));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(start_callback, audio, base::Passed(&video)));
 }
 
 void CastReceiverSession::StartAudio(
diff --git a/chrome/renderer/media/cast_session_browsertest.cc b/chrome/renderer/media/cast_session_browsertest.cc
index c9b0c43..f5db9b7 100644
--- a/chrome/renderer/media/cast_session_browsertest.cc
+++ b/chrome/renderer/media/cast_session_browsertest.cc
@@ -4,8 +4,8 @@
 
 #include "chrome/renderer/media/cast_session.h"
 
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/run_loop.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/renderer/chrome_content_renderer_client.h"
 #include "chrome/test/base/chrome_render_view_test.h"
 
@@ -17,7 +17,7 @@ typedef ChromeRenderViewTest CastSessionBrowserTest;
 // chrome renderer.
 TEST_F(CastSessionBrowserTest, CreateAndDestroy) {
   chrome_render_thread_->set_io_message_loop_proxy(
-      base::MessageLoopProxy::current());
+      base::ThreadTaskRunnerHandle::Get());
   ChromeContentRendererClient* client =
       static_cast<ChromeContentRendererClient*>(content_renderer_client_.get());
   client->RenderThreadStarted();
diff --git a/chrome/renderer/media/cast_threads.cc b/chrome/renderer/media/cast_threads.cc
index 9162ff2..b6c808c 100644
--- a/chrome/renderer/media/cast_threads.cc
+++ b/chrome/renderer/media/cast_threads.cc
@@ -5,6 +5,7 @@
 #include "chrome/renderer/media/cast_threads.h"
 
 #include "base/logging.h"
+#include "base/single_thread_task_runner.h"
 
 CastThreads::CastThreads()
     : audio_encode_thread_("CastAudioEncodeThread"),
@@ -15,10 +16,10 @@ CastThreads::CastThreads()
 
 scoped_refptr<base::SingleThreadTaskRunner>
 CastThreads::GetAudioEncodeMessageLoopProxy() {
-  return audio_encode_thread_.message_loop_proxy();
+  return audio_encode_thread_.task_runner();
 }
 
 scoped_refptr<base::SingleThreadTaskRunner>
 CastThreads::GetVideoEncodeMessageLoopProxy() {
-  return video_encode_thread_.message_loop_proxy();
+  return video_encode_thread_.task_runner();
 }
diff --git a/chrome/renderer/media/cast_transport_sender_ipc.h b/chrome/renderer/media/cast_transport_sender_ipc.h
index 21f87bd..ce18964 100644
--- a/chrome/renderer/media/cast_transport_sender_ipc.h
+++ b/chrome/renderer/media/cast_transport_sender_ipc.h
@@ -7,7 +7,7 @@
 
 #include <map>
 
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/thread_task_runner_handle.h"
 #include "ipc/ipc_channel_proxy.h"
 #include "media/cast/logging/logging_defines.h"
 #include "media/cast/net/cast_transport_sender.h"
diff --git a/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc b/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc
index 3760347..6680c7e 100644
--- a/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc
+++ b/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc
@@ -5,7 +5,9 @@
 #include <string>
 
 #include "base/bind.h"
+#include "base/location.h"
 #include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "chrome/renderer/media/chrome_webrtc_log_message_delegate.h"
 #include "chrome/renderer/media/mock_webrtc_logging_message_filter.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -14,7 +16,7 @@ TEST(ChromeWebRtcLogMessageDelegateTest, Basic) {
   const char kTestString[] = "abcdefghijklmnopqrstuvwxyz";
   base::MessageLoopForIO message_loop;
   scoped_refptr<MockWebRtcLoggingMessageFilter> log_message_filter(
-      new MockWebRtcLoggingMessageFilter(message_loop.message_loop_proxy()));
+      new MockWebRtcLoggingMessageFilter(message_loop.task_runner()));
   // Run message loop to initialize delegate.
   // TODO(vrk): Fix this so that we can construct a delegate without needing to
   // construct a message filter.
@@ -24,10 +26,9 @@ TEST(ChromeWebRtcLogMessageDelegateTest, Basic) {
       log_message_filter->log_message_delegate();
 
   // Start logging on the IO loop.
-  message_loop.message_loop_proxy()->PostTask(
-      FROM_HERE, base::Bind(
-          &ChromeWebRtcLogMessageDelegate::OnStartLogging,
-          base::Unretained(log_message_delegate)));
+  message_loop.task_runner()->PostTask(
+      FROM_HERE, base::Bind(&ChromeWebRtcLogMessageDelegate::OnStartLogging,
+                            base::Unretained(log_message_delegate)));
 
   // These log messages should be added to the log buffer outside of the IO
   // loop.
@@ -35,10 +36,9 @@ TEST(ChromeWebRtcLogMessageDelegateTest, Basic) {
   log_message_delegate->LogMessage(kTestString);
 
   // Stop logging on IO loop.
-  message_loop.message_loop_proxy()->PostTask(
-      FROM_HERE, base::Bind(
-          &ChromeWebRtcLogMessageDelegate::OnStopLogging,
-          base::Unretained(log_message_delegate)));
+  message_loop.task_runner()->PostTask(
+      FROM_HERE, base::Bind(&ChromeWebRtcLogMessageDelegate::OnStopLogging,
+                            base::Unretained(log_message_delegate)));
 
   // This log message should not be added to the log buffer.
   log_message_delegate->LogMessage(kTestString);
diff --git a/chrome/renderer/safe_browsing/phishing_classifier.cc b/chrome/renderer/safe_browsing/phishing_classifier.cc
index d731a76..e1d1926 100644
--- a/chrome/renderer/safe_browsing/phishing_classifier.cc
+++ b/chrome/renderer/safe_browsing/phishing_classifier.cc
@@ -9,10 +9,12 @@
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
+#include "base/location.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/safe_browsing/csd.pb.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/renderer/safe_browsing/feature_extractor_clock.h"
@@ -98,10 +100,9 @@ void PhishingClassifier::BeginClassification(
   // asynchronously, rather than directly from this method.  To ensure that
   // this is the case, post a task to begin feature extraction on the next
   // iteration of the message loop.
-  base::MessageLoop::current()->PostTask(
-      FROM_HERE,
-      base::Bind(&PhishingClassifier::BeginFeatureExtraction,
-                 weak_factory_.GetWeakPtr()));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(&PhishingClassifier::BeginFeatureExtraction,
+                            weak_factory_.GetWeakPtr()));
 }
 
 void PhishingClassifier::BeginFeatureExtraction() {
diff --git a/chrome/renderer/safe_browsing/phishing_classifier_delegate_browsertest.cc b/chrome/renderer/safe_browsing/phishing_classifier_delegate_browsertest.cc
index 50141be..fc973cd 100644
--- a/chrome/renderer/safe_browsing/phishing_classifier_delegate_browsertest.cc
+++ b/chrome/renderer/safe_browsing/phishing_classifier_delegate_browsertest.cc
@@ -5,8 +5,10 @@
 #include "chrome/renderer/safe_browsing/phishing_classifier_delegate.h"
 
 #include "base/command_line.h"
+#include "base/location.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/ui/browser.h"
@@ -118,7 +120,7 @@ class InterceptingMessageFilter : public content::BrowserMessageFilter {
         verdict->IsInitialized()) {
       verdict_.swap(verdict);
     }
-    waiting_message_loop_->PostTask(FROM_HERE, quit_closure_);
+    waiting_message_loop_->task_runner()->PostTask(FROM_HERE, quit_closure_);
   }
 
  private:
diff --git a/chrome/renderer/safe_browsing/phishing_dom_feature_extractor.cc b/chrome/renderer/safe_browsing/phishing_dom_feature_extractor.cc
index 9c92c9a..f47a186 100644
--- a/chrome/renderer/safe_browsing/phishing_dom_feature_extractor.cc
+++ b/chrome/renderer/safe_browsing/phishing_dom_feature_extractor.cc
@@ -7,10 +7,12 @@
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/containers/hash_tables.h"
+#include "base/location.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "chrome/renderer/safe_browsing/feature_extractor_clock.h"
 #include "chrome/renderer/safe_browsing/features.h"
@@ -133,7 +135,7 @@ void PhishingDOMFeatureExtractor::ExtractFeatures(
     cur_document_ = web_view->mainFrame()->document();
   }
 
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&PhishingDOMFeatureExtractor::ExtractFeaturesWithTimeout,
                  weak_factory_.GetWeakPtr()));
@@ -213,7 +215,7 @@ void PhishingDOMFeatureExtractor::ExtractFeaturesWithTimeout() {
           // clock granularity.
           UMA_HISTOGRAM_TIMES("SBClientPhishing.DOMFeatureChunkTime",
                               chunk_elapsed);
-          base::MessageLoop::current()->PostTask(
+          base::ThreadTaskRunnerHandle::Get()->PostTask(
               FROM_HERE,
               base::Bind(
                   &PhishingDOMFeatureExtractor::ExtractFeaturesWithTimeout,
diff --git a/chrome/renderer/safe_browsing/phishing_dom_feature_extractor_browsertest.cc b/chrome/renderer/safe_browsing/phishing_dom_feature_extractor_browsertest.cc
index 83746a0..c15219f 100644
--- a/chrome/renderer/safe_browsing/phishing_dom_feature_extractor_browsertest.cc
+++ b/chrome/renderer/safe_browsing/phishing_dom_feature_extractor_browsertest.cc
@@ -13,9 +13,11 @@
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
+#include "base/location.h"
 #include "base/memory/weak_ptr.h"
-#include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
@@ -62,10 +64,9 @@ class PhishingDOMFeatureExtractorTest : public InProcessBrowserTest {
   // Helper for the SubframeRemoval test that posts a message to remove
   // the iframe "frame1" from the document.
   void ScheduleRemoveIframe() {
-    base::MessageLoop::current()->PostTask(
-        FROM_HERE,
-        base::Bind(&PhishingDOMFeatureExtractorTest::RemoveIframe,
-                   weak_factory_.GetWeakPtr()));
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(&PhishingDOMFeatureExtractorTest::RemoveIframe,
+                              weak_factory_.GetWeakPtr()));
   }
 
  protected:
diff --git a/chrome/renderer/safe_browsing/phishing_term_feature_extractor.cc b/chrome/renderer/safe_browsing/phishing_term_feature_extractor.cc
index de488f4..31caf0b 100644
--- a/chrome/renderer/safe_browsing/phishing_term_feature_extractor.cc
+++ b/chrome/renderer/safe_browsing/phishing_term_feature_extractor.cc
@@ -11,11 +11,13 @@
 #include "base/compiler_specific.h"
 #include "base/i18n/break_iterator.h"
 #include "base/i18n/case_conversion.h"
+#include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "chrome/renderer/safe_browsing/feature_extractor_clock.h"
 #include "chrome/renderer/safe_browsing/features.h"
@@ -123,7 +125,7 @@ void PhishingTermFeatureExtractor::ExtractFeatures(
   done_callback_ = done_callback;
 
   state_.reset(new ExtractionState(*page_text_, clock_->Now()));
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&PhishingTermFeatureExtractor::ExtractFeaturesWithTimeout,
                  weak_factory_.GetWeakPtr()));
@@ -178,7 +180,7 @@ void PhishingTermFeatureExtractor::ExtractFeaturesWithTimeout() {
         // clock granularity.
         UMA_HISTOGRAM_TIMES("SBClientPhishing.TermFeatureChunkTime",
                             chunk_elapsed);
-        base::MessageLoop::current()->PostTask(
+        base::ThreadTaskRunnerHandle::Get()->PostTask(
             FROM_HERE,
             base::Bind(
                 &PhishingTermFeatureExtractor::ExtractFeaturesWithTimeout,
diff --git a/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc b/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
index 4c15605..7896758 100644
--- a/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
+++ b/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
@@ -9,8 +9,10 @@
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/containers/hash_tables.h"
+#include "base/location.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string16.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
@@ -110,10 +112,9 @@ class PhishingTermFeatureExtractorTest : public ::testing::Test {
         shingle_hashes,
         base::Bind(&PhishingTermFeatureExtractorTest::ExtractionDone,
                    base::Unretained(this)));
-    msg_loop_.PostTask(
-        FROM_HERE,
-        base::Bind(&PhishingTermFeatureExtractorTest::QuitExtraction,
-                   base::Unretained(this)));
+    msg_loop_.task_runner()->PostTask(
+        FROM_HERE, base::Bind(&PhishingTermFeatureExtractorTest::QuitExtraction,
+                              base::Unretained(this)));
     msg_loop_.RunUntilIdle();
   }
 
diff --git a/chrome/renderer/spellchecker/spellcheck.cc b/chrome/renderer/spellchecker/spellcheck.cc
index 4a0312a..a43c727 100644
--- a/chrome/renderer/spellchecker/spellcheck.cc
+++ b/chrome/renderer/spellchecker/spellcheck.cc
@@ -10,6 +10,8 @@
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/spellcheck_common.h"
 #include "chrome/common/spellcheck_messages.h"
 #include "chrome/common/spellcheck_result.h"
@@ -355,10 +357,9 @@ void SpellCheck::PostDelayedSpellCheckTask(SpellcheckRequest* request) {
   if (!request)
     return;
 
-  base::MessageLoopProxy::current()->PostTask(FROM_HERE,
-      base::Bind(&SpellCheck::PerformSpellCheck,
-                 AsWeakPtr(),
-                 base::Owned(request)));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(&SpellCheck::PerformSpellCheck, AsWeakPtr(),
+                            base::Owned(request)));
 }
 #endif
 
diff --git a/chrome/service/cloud_print/cloud_print_auth.cc b/chrome/service/cloud_print/cloud_print_auth.cc
index b52ba0c..663aca7 100644
--- a/chrome/service/cloud_print/cloud_print_auth.cc
+++ b/chrome/service/cloud_print/cloud_print_auth.cc
@@ -5,8 +5,11 @@
 #include "chrome/service/cloud_print/cloud_print_auth.h"
 
 #include "base/bind.h"
+#include "base/location.h"
 #include "base/metrics/histogram.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/common/cloud_print/cloud_print_helpers.h"
 #include "chrome/service/cloud_print/cloud_print_token_store.h"
@@ -134,9 +137,8 @@ void CloudPrintAuth::OnRefreshTokenResponse(const std::string& access_token,
   DCHECK(expires_in_seconds > kTokenRefreshGracePeriodSecs);
   base::TimeDelta refresh_delay = base::TimeDelta::FromSeconds(
       expires_in_seconds - kTokenRefreshGracePeriodSecs);
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&CloudPrintAuth::RefreshAccessToken, this),
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, base::Bind(&CloudPrintAuth::RefreshAccessToken, this),
       refresh_delay);
 }
 
diff --git a/chrome/service/cloud_print/cloud_print_connector.cc b/chrome/service/cloud_print/cloud_print_connector.cc
index 4abc4b4..fa78392 100644
--- a/chrome/service/cloud_print/cloud_print_connector.cc
+++ b/chrome/service/cloud_print/cloud_print_connector.cc
@@ -6,13 +6,16 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/location.h"
 #include "base/md5.h"
 #include "base/rand_util.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/common/cloud_print/cloud_print_helpers.h"
@@ -51,10 +54,9 @@ bool CloudPrintConnector::InitPrintSystem() {
 }
 
 void CloudPrintConnector::ScheduleStatsReport() {
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&CloudPrintConnector::ReportStats,
-                 stats_ptr_factory_.GetWeakPtr()),
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, base::Bind(&CloudPrintConnector::ReportStats,
+                            stats_ptr_factory_.GetWeakPtr()),
       base::TimeDelta::FromHours(1));
 }
 
@@ -492,7 +494,7 @@ void CloudPrintConnector::AddPendingTask(const PendingTask& task) {
   pending_tasks_.push_back(task);
   // If this is the only pending task, we need to start the process.
   if (pending_tasks_.size() == 1) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&CloudPrintConnector::ProcessPendingTask, this));
   }
 }
@@ -527,7 +529,7 @@ void CloudPrintConnector::ContinuePendingTaskProcessing() {
   // Delete current task and repost if we have more task available.
   pending_tasks_.pop_front();
   if (pending_tasks_.size() != 0) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&CloudPrintConnector::ProcessPendingTask, this));
   }
 }
diff --git a/chrome/service/cloud_print/cloud_print_proxy_backend.cc b/chrome/service/cloud_print/cloud_print_proxy_backend.cc
index 233ff2e..f93215d 100644
--- a/chrome/service/cloud_print/cloud_print_proxy_backend.cc
+++ b/chrome/service/cloud_print/cloud_print_proxy_backend.cc
@@ -10,9 +10,12 @@
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
+#include "base/location.h"
 #include "base/metrics/histogram.h"
 #include "base/rand_util.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/service/cloud_print/cloud_print_auth.h"
@@ -172,7 +175,7 @@ bool CloudPrintProxyBackend::InitializeWithToken(
     const std::string& cloud_print_token) {
   if (!core_thread_.Start())
     return false;
-  core_thread_.message_loop()->PostTask(
+  core_thread_.task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&CloudPrintProxyBackend::Core::DoInitializeWithToken,
                  core_.get(), cloud_print_token));
@@ -184,7 +187,7 @@ bool CloudPrintProxyBackend::InitializeWithRobotToken(
     const std::string& robot_email) {
   if (!core_thread_.Start())
     return false;
-  core_thread_.message_loop()->PostTask(
+  core_thread_.task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&CloudPrintProxyBackend::Core::DoInitializeWithRobotToken,
                  core_.get(), robot_oauth_refresh_token, robot_email));
@@ -196,7 +199,7 @@ bool CloudPrintProxyBackend::InitializeWithRobotAuthCode(
     const std::string& robot_email) {
   if (!core_thread_.Start())
     return false;
-  core_thread_.message_loop()->PostTask(
+  core_thread_.task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&CloudPrintProxyBackend::Core::DoInitializeWithRobotAuthCode,
                  core_.get(), robot_oauth_auth_code, robot_email));
@@ -204,7 +207,7 @@ bool CloudPrintProxyBackend::InitializeWithRobotAuthCode(
 }
 
 void CloudPrintProxyBackend::Shutdown() {
-  core_thread_.message_loop()->PostTask(
+  core_thread_.task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&CloudPrintProxyBackend::Core::DoShutdown, core_.get()));
   core_thread_.Stop();
@@ -212,10 +215,9 @@ void CloudPrintProxyBackend::Shutdown() {
 }
 
 void CloudPrintProxyBackend::UnregisterPrinters() {
-  core_thread_.message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(&CloudPrintProxyBackend::Core::DoUnregisterPrinters,
-                 core_.get()));
+  core_thread_.task_runner()->PostTask(
+      FROM_HERE, base::Bind(&CloudPrintProxyBackend::Core::DoUnregisterPrinters,
+                            core_.get()));
 }
 
 CloudPrintProxyBackend::Core::Core(
@@ -282,7 +284,7 @@ void CloudPrintProxyBackend::Core::OnAuthenticationComplete(
   token_store->SetToken(access_token);
   robot_email_ = robot_email;
   // Let the frontend know that we have authenticated.
-  backend_->frontend_loop_->PostTask(
+  backend_->frontend_loop_->task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&Core::NotifyAuthenticated, this, robot_oauth_refresh_token,
                  robot_email, user_email));
@@ -297,7 +299,7 @@ void CloudPrintProxyBackend::Core::OnAuthenticationComplete(
   if (!connector_->IsRunning()) {
     if (!connector_->Start()) {
       // Let the frontend know that we do not have a print system.
-      backend_->frontend_loop_->PostTask(
+      backend_->frontend_loop_->task_runner()->PostTask(
           FROM_HERE, base::Bind(&Core::NotifyPrintSystemUnavailable, this));
     }
   }
@@ -306,7 +308,7 @@ void CloudPrintProxyBackend::Core::OnAuthenticationComplete(
 void CloudPrintProxyBackend::Core::OnInvalidCredentials() {
   DCHECK(base::MessageLoop::current() == backend_->core_thread_.message_loop());
   VLOG(1) << "CP_CONNECTOR: Auth Error";
-  backend_->frontend_loop_->PostTask(
+  backend_->frontend_loop_->task_runner()->PostTask(
       FROM_HERE, base::Bind(&Core::NotifyAuthenticationFailed, this));
 }
 
@@ -323,9 +325,8 @@ void CloudPrintProxyBackend::Core::OnAuthFailed() {
 
 void CloudPrintProxyBackend::Core::OnXmppPingUpdated(int ping_timeout) {
   settings_.SetXmppPingTimeoutSec(ping_timeout);
-  backend_->frontend_loop_->PostTask(
-      FROM_HERE,
-      base::Bind(&Core::NotifyXmppPingUpdated, this, ping_timeout));
+  backend_->frontend_loop_->task_runner()->PostTask(
+      FROM_HERE, base::Bind(&Core::NotifyXmppPingUpdated, this, ping_timeout));
 }
 
 void CloudPrintProxyBackend::Core::InitNotifications(
@@ -379,10 +380,9 @@ void CloudPrintProxyBackend::Core::DoUnregisterPrinters() {
   std::list<std::string> printer_ids;
   connector_->GetPrinterIds(&printer_ids);
 
-  backend_->frontend_loop_->PostTask(
-      FROM_HERE,
-      base::Bind(&Core::NotifyUnregisterPrinters,
-                 this, access_token, printer_ids));
+  backend_->frontend_loop_->task_runner()->PostTask(
+      FROM_HERE, base::Bind(&Core::NotifyUnregisterPrinters, this, access_token,
+                            printer_ids));
 }
 
 void CloudPrintProxyBackend::Core::HandlePrinterNotification(
@@ -419,9 +419,8 @@ void CloudPrintProxyBackend::Core::ScheduleJobPoll() {
   if (!job_poll_scheduled_) {
     base::TimeDelta interval = base::TimeDelta::FromSeconds(
         base::RandInt(kMinJobPollIntervalSecs, kMaxJobPollIntervalSecs));
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&CloudPrintProxyBackend::Core::PollForJobs, this),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&CloudPrintProxyBackend::Core::PollForJobs, this),
         interval);
     job_poll_scheduled_ = true;
   }
@@ -438,7 +437,7 @@ void CloudPrintProxyBackend::Core::PingXmppServer() {
   pending_xmpp_pings_++;
   if (pending_xmpp_pings_ >= kMaxFailedXmppPings) {
     // Check ping status when we close to the limit.
-    base::MessageLoop::current()->PostDelayedTask(
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
         FROM_HERE,
         base::Bind(&CloudPrintProxyBackend::Core::CheckXmppPingStatus, this),
         base::TimeDelta::FromSeconds(kXmppPingCheckIntervalSecs));
@@ -456,7 +455,7 @@ void CloudPrintProxyBackend::Core::ScheduleXmppPing() {
     base::TimeDelta interval = base::TimeDelta::FromSeconds(
       base::RandInt(settings_.xmpp_ping_timeout_sec() * 0.9,
                     settings_.xmpp_ping_timeout_sec() * 1.1));
-    base::MessageLoop::current()->PostDelayedTask(
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
         FROM_HERE,
         base::Bind(&CloudPrintProxyBackend::Core::PingXmppServer, this),
         interval);
diff --git a/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc b/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc
index 60e0378..7d7c657 100644
--- a/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc
+++ b/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc
@@ -3,9 +3,11 @@
 // found in the LICENSE file.
 
 #include "base/command_line.h"
+#include "base/location.h"
 #include "base/memory/ref_counted.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/threading/thread.h"
 #include "base/values.h"
 #include "chrome/service/cloud_print/cloud_print_url_fetcher.h"
@@ -31,9 +33,9 @@ class TrackingTestURLRequestContextGetter
     : public net::TestURLRequestContextGetter {
  public:
   explicit TrackingTestURLRequestContextGetter(
-      base::MessageLoopProxy* io_message_loop_proxy,
+      base::SingleThreadTaskRunner* io_task_runner,
       net::URLRequestThrottlerManager* throttler_manager)
-      : TestURLRequestContextGetter(io_message_loop_proxy),
+      : TestURLRequestContextGetter(io_task_runner),
         throttler_manager_(throttler_manager) {
     g_request_context_getter_instances++;
   }
@@ -61,13 +63,12 @@ class TrackingTestURLRequestContextGetter
 class TestCloudPrintURLFetcher : public CloudPrintURLFetcher {
  public:
   explicit TestCloudPrintURLFetcher(
-      base::MessageLoopProxy* io_message_loop_proxy)
-      : io_message_loop_proxy_(io_message_loop_proxy) {
-  }
+      base::SingleThreadTaskRunner* io_task_runner)
+      : io_task_runner_(io_task_runner) {}
 
   net::URLRequestContextGetter* GetRequestContextGetter() override {
-    return new TrackingTestURLRequestContextGetter(
-        io_message_loop_proxy_.get(), throttler_manager());
+    return new TrackingTestURLRequestContextGetter(io_task_runner_.get(),
+                                                   throttler_manager());
   }
 
   net::URLRequestThrottlerManager* throttler_manager() {
@@ -77,7 +78,7 @@ class TestCloudPrintURLFetcher : public CloudPrintURLFetcher {
  private:
   ~TestCloudPrintURLFetcher() override {}
 
-  scoped_refptr<base::MessageLoopProxy> io_message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 
   // We set this as the throttler manager for the
   // TestURLRequestContext we create.
@@ -108,15 +109,15 @@ class CloudPrintURLFetcherTest : public testing::Test,
 
   std::string GetAuthHeader() override { return std::string(); }
 
-  scoped_refptr<base::MessageLoopProxy> io_message_loop_proxy() {
-    return io_message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner() {
+    return io_task_runner_;
   }
 
  protected:
   void SetUp() override {
     testing::Test::SetUp();
 
-    io_message_loop_proxy_ = base::MessageLoopProxy::current();
+    io_task_runner_ = base::ThreadTaskRunnerHandle::Get();
   }
 
   void TearDown() override {
@@ -133,7 +134,7 @@ class CloudPrintURLFetcherTest : public testing::Test,
   // dispatches its requests to.  When we wish to simulate being used from
   // a UI thread, we dispatch a worker thread to do so.
   base::MessageLoopForIO io_loop_;
-  scoped_refptr<base::MessageLoopProxy> io_message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
   int max_retries_;
   Time start_time_;
   scoped_refptr<TestCloudPrintURLFetcher> fetcher_;
@@ -210,7 +211,7 @@ class CloudPrintURLFetcherRetryBackoffTest : public CloudPrintURLFetcherTest {
 
 
 void CloudPrintURLFetcherTest::CreateFetcher(const GURL& url, int max_retries) {
-  fetcher_ = new TestCloudPrintURLFetcher(io_message_loop_proxy().get());
+  fetcher_ = new TestCloudPrintURLFetcher(io_task_runner().get());
 
   // Registers an entry for test url. It only allows 3 requests to be sent
   // in 200 milliseconds.
@@ -254,8 +255,7 @@ CloudPrintURLFetcherBasicTest::HandleRawResponse(
   if (handle_raw_response_) {
     // If the current message loop is not the IO loop, it will be shut down when
     // the main loop returns and this thread subsequently goes out of scope.
-    io_message_loop_proxy()->PostTask(FROM_HERE,
-                                      base::MessageLoop::QuitClosure());
+    io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
     return CloudPrintURLFetcher::STOP_PROCESSING;
   }
   return CloudPrintURLFetcher::CONTINUE_PROCESSING;
@@ -269,8 +269,7 @@ CloudPrintURLFetcherBasicTest::HandleRawData(
   // We should never get here if we returned true in HandleRawResponse
   EXPECT_FALSE(handle_raw_response_);
   if (handle_raw_data_) {
-    io_message_loop_proxy()->PostTask(FROM_HERE,
-                                      base::MessageLoop::QuitClosure());
+    io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
     return CloudPrintURLFetcher::STOP_PROCESSING;
   }
   return CloudPrintURLFetcher::CONTINUE_PROCESSING;
@@ -285,8 +284,7 @@ CloudPrintURLFetcherBasicTest::HandleJSONData(
   // We should never get here if we returned true in one of the above methods.
   EXPECT_FALSE(handle_raw_response_);
   EXPECT_FALSE(handle_raw_data_);
-  io_message_loop_proxy()->PostTask(FROM_HERE,
-                                    base::MessageLoop::QuitClosure());
+  io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
 
@@ -304,8 +302,7 @@ CloudPrintURLFetcherOverloadTest::HandleRawData(
     // We have already sent 20 requests continuously. And we expect that
     // it takes more than 1 second due to the overload protection settings.
     EXPECT_TRUE(Time::Now() - start_time_ >= one_second);
-    io_message_loop_proxy()->PostTask(FROM_HERE,
-                                      base::MessageLoop::QuitClosure());
+    io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
   }
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
@@ -324,8 +321,7 @@ CloudPrintURLFetcherRetryBackoffTest::HandleRawData(
 void CloudPrintURLFetcherRetryBackoffTest::OnRequestGiveUp() {
   // It takes more than 200 ms to finish all 11 requests.
   EXPECT_TRUE(Time::Now() - start_time_ >= TimeDelta::FromMilliseconds(200));
-  io_message_loop_proxy()->PostTask(FROM_HERE,
-                                    base::MessageLoop::QuitClosure());
+  io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
 }
 
 TEST_F(CloudPrintURLFetcherBasicTest, HandleRawResponse) {
diff --git a/chrome/service/cloud_print/connector_settings_unittest.cc b/chrome/service/cloud_print/connector_settings_unittest.cc
index 5239fd2..b8475fb 100644
--- a/chrome/service/cloud_print/connector_settings_unittest.cc
+++ b/chrome/service/cloud_print/connector_settings_unittest.cc
@@ -9,7 +9,8 @@
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/service/service_process_prefs.h"
@@ -50,7 +51,7 @@ class ConnectorSettingsTest : public testing::Test {
  protected:
   void SetUp() override {
     ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
-    message_loop_proxy_ = base::MessageLoopProxy::current();
+    task_runner_ = base::ThreadTaskRunnerHandle::Get();
   }
 
   ServiceProcessPrefs* CreateTestFile(const char* json) {
@@ -62,14 +63,14 @@ class ConnectorSettingsTest : public testing::Test {
       base::WriteFile(file_name, content.c_str(), content.size());
     }
     ServiceProcessPrefs* prefs =
-        new ServiceProcessPrefs(file_name, message_loop_proxy_.get());
+        new ServiceProcessPrefs(file_name, task_runner_.get());
     prefs->ReadPrefs();
     return prefs;
   }
 
   base::ScopedTempDir temp_dir_;
   base::MessageLoop message_loop_;
-  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 };
 
 TEST_F(ConnectorSettingsTest, InitFromEmpty) {
diff --git a/chrome/service/cloud_print/job_status_updater.cc b/chrome/service/cloud_print/job_status_updater.cc
index dcdca08..840bfc0 100644
--- a/chrome/service/cloud_print/job_status_updater.cc
+++ b/chrome/service/cloud_print/job_status_updater.cc
@@ -6,9 +6,12 @@
 
 #include "base/bind.h"
 #include "base/json/json_reader.h"
+#include "base/location.h"
 #include "base/metrics/histogram.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/service/cloud_print/cloud_print_service_helpers.h"
@@ -100,7 +103,7 @@ CloudPrintURLFetcher::ResponseAction JobStatusUpdater::HandleJSONData(
       base::DictionaryValue* json_data,
       bool succeeded) {
   if (IsTerminalJobState(last_job_details_.status)) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&JobStatusUpdater::Stop, this));
   }
   return CloudPrintURLFetcher::STOP_PROCESSING;
diff --git a/chrome/service/cloud_print/print_system_cups.cc b/chrome/service/cloud_print/print_system_cups.cc
index 132a252..86b453a 100644
--- a/chrome/service/cloud_print/print_system_cups.cc
+++ b/chrome/service/cloud_print/print_system_cups.cc
@@ -16,14 +16,16 @@
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/json/json_reader.h"
+#include "base/location.h"
 #include "base/logging.h"
 #include "base/md5.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/message_loop/message_loop.h"
 #include "base/rand_util.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/common/crash_keys.h"
@@ -183,9 +185,8 @@ class PrintServerWatcherCUPS
       PrintSystem::PrintServerWatcher::Delegate* delegate) override {
     delegate_ = delegate;
     printers_hash_ = GetPrintersHash();
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrintServerWatcherCUPS::CheckForUpdates, this),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&PrintServerWatcherCUPS::CheckForUpdates, this),
         print_system_->GetUpdateTimeout());
     return true;
   }
@@ -204,9 +205,8 @@ class PrintServerWatcherCUPS
       printers_hash_ = new_hash;
       delegate_->OnPrinterAdded();
     }
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrintServerWatcherCUPS::CheckForUpdates, this),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&PrintServerWatcherCUPS::CheckForUpdates, this),
         print_system_->GetUpdateTimeout());
   }
 
@@ -260,15 +260,13 @@ class PrinterWatcherCUPS
     delegate_ = delegate;
     settings_hash_ = GetSettingsHash();
     // Schedule next job status update.
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrinterWatcherCUPS::JobStatusUpdate, this),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&PrinterWatcherCUPS::JobStatusUpdate, this),
         base::TimeDelta::FromSeconds(kJobUpdateTimeoutSeconds));
     // Schedule next printer check.
     // TODO(gene): Randomize time for the next printer update.
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrinterWatcherCUPS::PrinterUpdate, this),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&PrinterWatcherCUPS::PrinterUpdate, this),
         print_system_->GetUpdateTimeout());
     return true;
   }
@@ -292,9 +290,8 @@ class PrinterWatcherCUPS
     // jobs for this printer and check their status. If printer has no
     // outstanding jobs, OnJobChanged() will do nothing.
     delegate_->OnJobChanged();
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrinterWatcherCUPS::JobStatusUpdate, this),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&PrinterWatcherCUPS::JobStatusUpdate, this),
         base::TimeDelta::FromSeconds(kJobUpdateTimeoutSeconds));
   }
 
@@ -317,9 +314,8 @@ class PrinterWatcherCUPS
                 << ", printer name: " << printer_name_;
       }
     }
-    base::MessageLoop::current()->PostDelayedTask(
-        FROM_HERE,
-        base::Bind(&PrinterWatcherCUPS::PrinterUpdate, this),
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&PrinterWatcherCUPS::PrinterUpdate, this),
         print_system_->GetUpdateTimeout());
   }
 
@@ -380,7 +376,7 @@ class JobSpoolerCUPS : public PrintSystem::JobSpooler {
     int job_id = print_system_->SpoolPrintJob(
         print_ticket, print_data_file_path, print_data_mime_type,
         printer_name, job_title, tags, &dry_run);
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::Bind(&JobSpoolerCUPS::NotifyDelegate, delegate, job_id, dry_run));
     return true;
@@ -498,9 +494,8 @@ void PrintSystemCUPS::UpdatePrinters() {
   }
 
   // Schedule next update.
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&PrintSystemCUPS::UpdatePrinters, this),
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, base::Bind(&PrintSystemCUPS::UpdatePrinters, this),
       GetUpdateTimeout());
 }
 
@@ -524,13 +519,9 @@ void PrintSystemCUPS::GetPrinterCapsAndDefaults(
     const PrinterCapsAndDefaultsCallback& callback) {
   printing::PrinterCapsAndDefaults printer_info;
   bool succeeded = GetPrinterCapsAndDefaults(printer_name, &printer_info);
-  base::MessageLoop::current()->PostTask(
-      FROM_HERE,
-      base::Bind(&PrintSystemCUPS::RunCapsCallback,
-                 callback,
-                 succeeded,
-                 printer_name,
-                 printer_info));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(&PrintSystemCUPS::RunCapsCallback, callback,
+                            succeeded, printer_name, printer_info));
 }
 
 bool PrintSystemCUPS::IsValidPrinter(const std::string& printer_name) {
diff --git a/chrome/service/cloud_print/print_system_win.cc b/chrome/service/cloud_print/print_system_win.cc
index 550a5633..58b5231 100644
--- a/chrome/service/cloud_print/print_system_win.cc
+++ b/chrome/service/cloud_print/print_system_win.cc
@@ -9,6 +9,7 @@
 #include "base/json/json_writer.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/win/object_watcher.h"
 #include "base/win/scoped_bstr.h"
 #include "base/win/scoped_comptr.h"
@@ -410,26 +411,24 @@ class JobSpoolerWin : public PrintSystem::JobSpooler {
       int dc_width = GetDeviceCaps(printer_dc_.Get(), PHYSICALWIDTH);
       int dc_height = GetDeviceCaps(printer_dc_.Get(), PHYSICALHEIGHT);
       gfx::Rect render_area(0, 0, dc_width, dc_height);
-      g_service_process->io_thread()->message_loop_proxy()->PostTask(
+      g_service_process->io_thread()->task_runner()->PostTask(
           FROM_HERE,
-          base::Bind(&JobSpoolerWin::Core::RenderPDFPagesInSandbox,
-                     this,
-                     print_data_file_path_,
-                     render_area,
-                     printer_dpi,
-                     base::MessageLoopProxy::current()));
+          base::Bind(&JobSpoolerWin::Core::RenderPDFPagesInSandbox, this,
+                     print_data_file_path_, render_area, printer_dpi,
+                     base::ThreadTaskRunnerHandle::Get()));
     }
 
     // Called on the service process IO thread.
-    void RenderPDFPagesInSandbox(const base::FilePath& pdf_path,
-                                 const gfx::Rect& render_area,
-                                 int render_dpi,
-                                 const scoped_refptr<base::MessageLoopProxy>&
-                                     client_message_loop_proxy) {
-      DCHECK(g_service_process->io_thread()->message_loop_proxy()->
-          BelongsToCurrentThread());
+    void RenderPDFPagesInSandbox(
+        const base::FilePath& pdf_path,
+        const gfx::Rect& render_area,
+        int render_dpi,
+        const scoped_refptr<base::SingleThreadTaskRunner>& client_task_runner) {
+      DCHECK(g_service_process->io_thread()
+                 ->task_runner()
+                 ->BelongsToCurrentThread());
       scoped_ptr<ServiceUtilityProcessHost> utility_host(
-          new ServiceUtilityProcessHost(this, client_message_loop_proxy.get()));
+          new ServiceUtilityProcessHost(this, client_task_runner.get()));
       // TODO(gene): For now we disabling autorotation for CloudPrinting.
       // Landscape/Portrait setting is passed in the print ticket and
       // server is generating portrait PDF always.
@@ -441,7 +440,7 @@ class JobSpoolerWin : public PrintSystem::JobSpooler {
         // The object will self-destruct when the child process dies.
         utility_host.release();
       } else {
-        client_message_loop_proxy->PostTask(
+        client_task_runner->PostTask(
             FROM_HERE, base::Bind(&Core::PrintJobDone, this, false));
       }
     }
@@ -555,53 +554,51 @@ class PrinterCapsHandler : public ServiceUtilityProcessHost::Client {
   }
 
   void StartGetPrinterCapsAndDefaults() {
-    g_service_process->io_thread()->message_loop_proxy()->PostTask(
+    g_service_process->io_thread()->task_runner()->PostTask(
         FROM_HERE,
         base::Bind(&PrinterCapsHandler::GetPrinterCapsAndDefaultsImpl, this,
-                    base::MessageLoopProxy::current()));
+                   base::ThreadTaskRunnerHandle::Get()));
   }
 
   void StartGetPrinterSemanticCapsAndDefaults() {
-    g_service_process->io_thread()->message_loop_proxy()->PostTask(
+    g_service_process->io_thread()->task_runner()->PostTask(
         FROM_HERE,
         base::Bind(&PrinterCapsHandler::GetPrinterSemanticCapsAndDefaultsImpl,
-                   this, base::MessageLoopProxy::current()));
+                   this, base::ThreadTaskRunnerHandle::Get()));
   }
 
  private:
   ~PrinterCapsHandler() override {}
 
   void GetPrinterCapsAndDefaultsImpl(
-      const scoped_refptr<base::MessageLoopProxy>&
-          client_message_loop_proxy) {
-    DCHECK(g_service_process->io_thread()->message_loop_proxy()->
-        BelongsToCurrentThread());
+      const scoped_refptr<base::SingleThreadTaskRunner>& client_task_runner) {
+    DCHECK(g_service_process->io_thread()
+               ->task_runner()
+               ->BelongsToCurrentThread());
     scoped_ptr<ServiceUtilityProcessHost> utility_host(
-        new ServiceUtilityProcessHost(this, client_message_loop_proxy.get()));
+        new ServiceUtilityProcessHost(this, client_task_runner.get()));
     if (utility_host->StartGetPrinterCapsAndDefaults(printer_name_)) {
       // The object will self-destruct when the child process dies.
       utility_host.release();
     } else {
-      client_message_loop_proxy->PostTask(
-          FROM_HERE,
-          base::Bind(&PrinterCapsHandler::OnChildDied, this));
+      client_task_runner->PostTask(
+          FROM_HERE, base::Bind(&PrinterCapsHandler::OnChildDied, this));
     }
   }
 
   void GetPrinterSemanticCapsAndDefaultsImpl(
-      const scoped_refptr<base::MessageLoopProxy>&
-          client_message_loop_proxy) {
-    DCHECK(g_service_process->io_thread()->message_loop_proxy()->
-        BelongsToCurrentThread());
+      const scoped_refptr<base::SingleThreadTaskRunner>& client_task_runner) {
+    DCHECK(g_service_process->io_thread()
+               ->task_runner()
+               ->BelongsToCurrentThread());
     scoped_ptr<ServiceUtilityProcessHost> utility_host(
-        new ServiceUtilityProcessHost(this, client_message_loop_proxy.get()));
+        new ServiceUtilityProcessHost(this, client_task_runner.get()));
     if (utility_host->StartGetPrinterSemanticCapsAndDefaults(printer_name_)) {
       // The object will self-destruct when the child process dies.
       utility_host.release();
     } else {
-      client_message_loop_proxy->PostTask(
-          FROM_HERE,
-          base::Bind(&PrinterCapsHandler::OnChildDied, this));
+      client_task_runner->PostTask(
+          FROM_HERE, base::Bind(&PrinterCapsHandler::OnChildDied, this));
     }
   }
 
diff --git a/chrome/service/cloud_print/printer_job_handler.cc b/chrome/service/cloud_print/printer_job_handler.cc
index 95dfb55..f57ceb6 100644
--- a/chrome/service/cloud_print/printer_job_handler.cc
+++ b/chrome/service/cloud_print/printer_job_handler.cc
@@ -8,10 +8,12 @@
 #include "base/bind_helpers.h"
 #include "base/files/file_util.h"
 #include "base/json/json_reader.h"
+#include "base/location.h"
 #include "base/md5.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/common/cloud_print/cloud_print_helpers.h"
@@ -72,8 +74,7 @@ PrinterJobHandler::PrinterJobHandler(
       next_json_data_handler_(NULL),
       next_data_handler_(NULL),
       print_thread_("Chrome_CloudPrintJobPrintThread"),
-      job_handler_message_loop_proxy_(
-          base::MessageLoopProxy::current()),
+      job_handler_task_runner_(base::ThreadTaskRunnerHandle::Get()),
       shutting_down_(false),
       job_check_pending_(false),
       printer_update_pending_(true),
@@ -106,7 +107,7 @@ void PrinterJobHandler::CheckForJobs(const std::string& reason) {
   job_fetch_reason_ = reason;
   job_check_pending_ = true;
   if (!task_in_progress_) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&PrinterJobHandler::Start, this));
   }
 }
@@ -136,7 +137,7 @@ CloudPrintURLFetcher::ResponseAction PrinterJobHandler::HandleRawResponse(
   if (next_data_handler_ == (&PrinterJobHandler::HandlePrintDataResponse) &&
       response_code == net::HTTP_UNSUPPORTED_MEDIA_TYPE) {
     VLOG(1) << "CP_CONNECTOR: Job failed (unsupported media type)";
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::Bind(&PrinterJobHandler::JobFailed, this, JOB_DOWNLOAD_FAILED));
     return CloudPrintURLFetcher::STOP_PROCESSING;
@@ -167,12 +168,12 @@ void PrinterJobHandler::OnRequestGiveUp() {
   if (job_queue_handler_.JobFetchFailed(job_details_.job_id_)) {
     VLOG(1) << "CP_CONNECTOR: Job failed to load (scheduling retry)";
     CheckForJobs(kJobFetchReasonFailure);
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&PrinterJobHandler::Stop, this));
   } else {
     VLOG(1) << "CP_CONNECTOR: Job failed (giving up after " <<
         kNumRetriesBeforeAbandonJob << " retries)";
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::Bind(&PrinterJobHandler::JobFailed, this, JOB_DOWNLOAD_FAILED));
   }
@@ -213,7 +214,7 @@ bool PrinterJobHandler::OnJobCompleted(JobStatusUpdater* updater) {
 }
 
 void PrinterJobHandler::OnAuthError() {
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&PrinterJobHandler::Stop, this));
   if (delegate_)
     delegate_->OnAuthError();
@@ -227,7 +228,7 @@ void PrinterJobHandler::OnPrinterDeleted() {
 void PrinterJobHandler::OnPrinterChanged() {
   printer_update_pending_ = true;
   if (!task_in_progress_) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&PrinterJobHandler::Start, this));
   }
 }
@@ -237,7 +238,7 @@ void PrinterJobHandler::OnJobChanged() {
   // and have them check for updates.
   for (JobStatusUpdaterList::iterator index = job_status_updater_list_.begin();
        index != job_status_updater_list_.end(); index++) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&JobStatusUpdater::UpdateStatus, index->get()));
   }
 }
@@ -247,7 +248,7 @@ void PrinterJobHandler::OnJobSpoolSucceeded(const PlatformJobId& job_id) {
   job_spooler_->AddRef();
   print_thread_.message_loop()->ReleaseSoon(FROM_HERE, job_spooler_.get());
   job_spooler_ = NULL;
-  job_handler_message_loop_proxy_->PostTask(
+  job_handler_task_runner_->PostTask(
       FROM_HERE, base::Bind(&PrinterJobHandler::JobSpooled, this, job_id));
 }
 
@@ -257,7 +258,7 @@ void PrinterJobHandler::OnJobSpoolFailed() {
   print_thread_.message_loop()->ReleaseSoon(FROM_HERE, job_spooler_.get());
   job_spooler_ = NULL;
   VLOG(1) << "CP_CONNECTOR: Job failed (spool failed)";
-  job_handler_message_loop_proxy_->PostTask(
+  job_handler_task_runner_->PostTask(
       FROM_HERE, base::Bind(&PrinterJobHandler::JobFailed, this, JOB_FAILED));
 }
 
@@ -288,7 +289,7 @@ PrinterJobHandler::HandlePrinterUpdateResponse(
   // We are done here. Go to the Stop state
   VLOG(1) << "CP_CONNECTOR: Stopping printer job handler"
           << ", printer id: " << printer_info_cloud_.printer_id;
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&PrinterJobHandler::Stop, this));
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
@@ -329,7 +330,7 @@ PrinterJobHandler::HandleJobMetadataResponse(
         }
       } else {
         job_available = false;
-        base::MessageLoop::current()->PostDelayedTask(
+        base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
             FROM_HERE,
             base::Bind(&PrinterJobHandler::RunScheduledJobCheck, this),
             jobs[0].time_remaining_);
@@ -341,7 +342,7 @@ PrinterJobHandler::HandleJobMetadataResponse(
     // If no jobs are available, go to the Stop state.
     VLOG(1) << "CP_CONNECTOR: Stopping printer job handler"
             << ", printer id: " << printer_info_cloud_.printer_id;
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&PrinterJobHandler::Stop, this));
   }
   return CloudPrintURLFetcher::STOP_PROCESSING;
@@ -403,9 +404,9 @@ PrinterJobHandler::HandlePrintDataResponse(const net::URLFetcher* source,
   // here.
   VLOG(1) << "CP_CONNECTOR: Error saving print data"
           << ", printer id: " << printer_info_cloud_.printer_id;
-  base::MessageLoop::current()->PostTask(
-      FROM_HERE, base::Bind(&PrinterJobHandler::JobFailed, this,
-                            JOB_DOWNLOAD_FAILED));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE,
+      base::Bind(&PrinterJobHandler::JobFailed, this, JOB_DOWNLOAD_FAILED));
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
 
@@ -417,7 +418,7 @@ PrinterJobHandler::HandleInProgressStatusUpdateResponse(
     bool succeeded) {
   VLOG(1) << "CP_CONNECTOR: Handling success status update response"
           << ", printer id: " << printer_info_cloud_.printer_id;
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&PrinterJobHandler::StartPrinting, this));
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
@@ -430,7 +431,7 @@ PrinterJobHandler::HandleFailureStatusUpdateResponse(
     bool succeeded) {
   VLOG(1) << "CP_CONNECTOR: Handling failure status update response"
           << ", printer id: " << printer_info_cloud_.printer_id;
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&PrinterJobHandler::Stop, this));
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
@@ -499,7 +500,7 @@ void PrinterJobHandler::Stop() {
           << ", task in progress: " << task_in_progress_;
   Reset();
   if (HavePendingTasks()) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&PrinterJobHandler::Start, this));
   }
 }
@@ -520,7 +521,7 @@ void PrinterJobHandler::StartPrinting() {
               << ", printer id: " << printer_info_cloud_.printer_id;
       JobFailed(JOB_FAILED);
     } else {
-      print_thread_.message_loop()->PostTask(
+      print_thread_.task_runner()->PostTask(
           FROM_HERE, base::Bind(&PrinterJobHandler::DoPrint, this, job_details_,
                                 printer_info_.printer_name));
     }
@@ -619,7 +620,7 @@ void PrinterJobHandler::JobSpooled(PlatformJobId local_job_id) {
                             local_job_id_, cloud_print_server_url_,
                             print_system_.get(), this));
   job_status_updater_list_.push_back(job_status_updater);
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&JobStatusUpdater::UpdateStatus, job_status_updater.get()));
 
@@ -627,7 +628,7 @@ void PrinterJobHandler::JobSpooled(PlatformJobId local_job_id) {
 
   VLOG(1) << "CP_CONNECTOR: Stopping printer job handler"
           << ", printer id: " << printer_info_cloud_.printer_id;
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&PrinterJobHandler::Stop, this));
 }
 
@@ -774,13 +775,13 @@ void PrinterJobHandler::OnReceivePrinterCaps(
     // We are done here. Go to the Stop state
     VLOG(1) << "CP_CONNECTOR: Stopping printer job handler"
             << ", printer name: " << printer_name;
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(&PrinterJobHandler::Stop, this));
   }
 }
 
 // The following methods are called on |print_thread_|. It is not safe to
-// access any members other than |job_handler_message_loop_proxy_|,
+// access any members other than |job_handler_task_runner_|,
 // |job_spooler_| and |print_system_|.
 void PrinterJobHandler::DoPrint(const JobDetails& job_details,
                                 const std::string& printer_name) {
diff --git a/chrome/service/cloud_print/printer_job_handler.h b/chrome/service/cloud_print/printer_job_handler.h
index 304e2bc..c49ee45 100644
--- a/chrome/service/cloud_print/printer_job_handler.h
+++ b/chrome/service/cloud_print/printer_job_handler.h
@@ -12,7 +12,7 @@
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
 #include "base/threading/thread.h"
 #include "base/time/time.h"
 #include "chrome/service/cloud_print/cloud_print_url_fetcher.h"
@@ -275,7 +275,7 @@ class PrinterJobHandler : public base::RefCountedThreadSafe<PrinterJobHandler>,
   scoped_refptr<PrintSystem::JobSpooler> job_spooler_;
   // The message loop proxy representing the thread on which this object
   // was created. Used by the print thread.
-  scoped_refptr<base::MessageLoopProxy> job_handler_message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> job_handler_task_runner_;
 
   // There may be pending tasks in the message queue when Shutdown is called.
   // We set this flag so as to do nothing in those tasks.
diff --git a/chrome/service/cloud_print/printer_job_handler_unittest.cc b/chrome/service/cloud_print/printer_job_handler_unittest.cc
index a7147ef..da396dd 100644
--- a/chrome/service/cloud_print/printer_job_handler_unittest.cc
+++ b/chrome/service/cloud_print/printer_job_handler_unittest.cc
@@ -3,12 +3,14 @@
 // found in the LICENSE file.
 
 #include "base/files/file_path.h"
+#include "base/location.h"
 #include "base/md5.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/cloud_print/cloud_print_constants.h"
 #include "chrome/service/cloud_print/cloud_print_service_helpers.h"
 #include "chrome/service/cloud_print/cloud_print_token_store.h"
@@ -247,9 +249,10 @@ std::string StatusResponse(int job_num, const char* status_string) {
 class CloudPrintURLFetcherNoServiceProcess
     : public CloudPrintURLFetcher {
  public:
-  CloudPrintURLFetcherNoServiceProcess() :
-      context_getter_(new net::TestURLRequestContextGetter(
-          base::MessageLoopProxy::current())) {}
+  CloudPrintURLFetcherNoServiceProcess()
+      : context_getter_(new net::TestURLRequestContextGetter(
+            base::ThreadTaskRunnerHandle::Get())) {}
+
  protected:
   net::URLRequestContextGetter* GetRequestContextGetter() override {
     return context_getter_.get();
@@ -522,7 +525,7 @@ void PrinterJobHandlerTest::MessageLoopQuitNowHelper(
 
 void PrinterJobHandlerTest::MessageLoopQuitSoonHelper(
     base::MessageLoop* message_loop) {
-  message_loop->message_loop_proxy()->PostTask(
+  message_loop->task_runner()->PostTask(
       FROM_HERE, base::Bind(&MessageLoopQuitNowHelper, message_loop));
 }
 
@@ -532,14 +535,14 @@ PrinterJobHandlerTest::PrinterJobHandlerTest()
 }
 
 bool PrinterJobHandlerTest::PostSpoolSuccess() {
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&PrinterJobHandler::OnJobSpoolSucceeded, job_handler_, 0));
 
   // Everything that would be posted on the printer thread queue
   // has been posted, we can tell the main message loop to quit when idle
   // and not worry about it idling while the print thread does work
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&MessageLoopQuitSoonHelper, &loop_));
   return true;
 }
@@ -769,15 +772,12 @@ TEST_F(PrinterJobHandlerTest, DISABLED_ManyFailureTest) {
                            net::HTTP_INTERNAL_SERVER_ERROR,
                            net::URLRequestStatus::FAILED);
 
-  loop_.PostDelayedTask(FROM_HERE,
-                        base::Bind(&net::FakeURLFetcherFactory::SetFakeResponse,
-                                   base::Unretained(&factory_),
-                                   TicketURI(1),
-                                   kExamplePrintTicket,
-                                   net::HTTP_OK,
-                                   net::URLRequestStatus::SUCCESS),
-                        base::TimeDelta::FromSeconds(1));
-
+  loop_.task_runner()->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(&net::FakeURLFetcherFactory::SetFakeResponse,
+                 base::Unretained(&factory_), TicketURI(1), kExamplePrintTicket,
+                 net::HTTP_OK, net::URLRequestStatus::SUCCESS),
+      base::TimeDelta::FromSeconds(1));
 
   BeginTest(5);
 }
diff --git a/chrome/service/net/service_url_request_context_getter.cc b/chrome/service/net/service_url_request_context_getter.cc
index cd75264..3dfbd2b 100644
--- a/chrome/service/net/service_url_request_context_getter.cc
+++ b/chrome/service/net/service_url_request_context_getter.cc
@@ -9,7 +9,7 @@
 #endif
 
 #include "base/compiler_specific.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/sys_info.h"
 #include "chrome/common/chrome_version_info.h"
@@ -96,14 +96,13 @@ std::string MakeUserAgentForServiceProcess() {
 
 ServiceURLRequestContextGetter::ServiceURLRequestContextGetter()
     : user_agent_(MakeUserAgentForServiceProcess()),
-      network_task_runner_(
-          g_service_process->io_thread()->message_loop_proxy()) {
+      network_task_runner_(g_service_process->io_thread()->task_runner()) {
   // TODO(sanjeevr): Change CreateSystemProxyConfigService to accept a
-  // MessageLoopProxy* instead of MessageLoop*.
+  // SingleThreadTaskRunner* instead of MessageLoop*.
   DCHECK(g_service_process);
   proxy_config_service_.reset(net::ProxyService::CreateSystemProxyConfigService(
-      g_service_process->io_thread()->message_loop_proxy(),
-      g_service_process->file_thread()->message_loop_proxy()));
+      g_service_process->io_thread()->task_runner(),
+      g_service_process->file_thread()->task_runner()));
 }
 
 net::URLRequestContext*
diff --git a/chrome/service/net/service_url_request_context_getter.h b/chrome/service/net/service_url_request_context_getter.h
index cd50265..caf439c 100644
--- a/chrome/service/net/service_url_request_context_getter.h
+++ b/chrome/service/net/service_url_request_context_getter.h
@@ -21,7 +21,7 @@
 #include "net/url_request/url_request_context_storage.h"
 
 namespace base {
-class MessageLoopProxy;
+class SingleThreadTaskRunner;
 }
 
 namespace net {
diff --git a/chrome/service/service_ipc_server.cc b/chrome/service/service_ipc_server.cc
index 3265b9e..4558242 100644
--- a/chrome/service/service_ipc_server.cc
+++ b/chrome/service/service_ipc_server.cc
@@ -27,11 +27,8 @@ bool ServiceIPCServer::Init() {
 void ServiceIPCServer::CreateChannel() {
   channel_.reset(NULL); // Tear down the existing channel, if any.
   channel_ = IPC::SyncChannel::Create(
-      channel_handle_,
-      IPC::Channel::MODE_NAMED_SERVER,
-      this,
-      g_service_process->io_thread()->message_loop_proxy().get(),
-      true,
+      channel_handle_, IPC::Channel::MODE_NAMED_SERVER, this,
+      g_service_process->io_thread()->task_runner().get(), true,
       g_service_process->shutdown_event());
   DCHECK(sync_message_filter_.get());
   channel_->AddFilter(sync_message_filter_.get());
diff --git a/chrome/service/service_process.cc b/chrome/service/service_process.cc
index 3bed9fe..79d3ba0 100644
--- a/chrome/service/service_process.cc
+++ b/chrome/service/service_process.cc
@@ -11,11 +11,14 @@
 #include "base/command_line.h"
 #include "base/environment.h"
 #include "base/i18n/rtl.h"
+#include "base/location.h"
 #include "base/memory/singleton.h"
 #include "base/path_service.h"
 #include "base/prefs/json_pref_store.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
@@ -193,7 +196,7 @@ bool ServiceProcess::Initialize(base::MessageLoopForUI* message_loop,
   // After the IPC server has started we signal that the service process is
   // ready.
   if (!service_process_state_->SignalReady(
-          io_thread_->message_loop_proxy().get(),
+          io_thread_->task_runner().get(),
           base::Bind(&ServiceProcess::Terminate, base::Unretained(this)))) {
     return false;
   }
@@ -253,7 +256,8 @@ void ServiceProcess::Shutdown() {
 }
 
 void ServiceProcess::Terminate() {
-  main_message_loop_->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+  main_message_loop_->task_runner()->PostTask(FROM_HERE,
+                                              base::MessageLoop::QuitClosure());
 }
 
 bool ServiceProcess::HandleClientDisconnect() {
@@ -325,7 +329,7 @@ void ServiceProcess::OnServiceDisabled() {
 }
 
 void ServiceProcess::ScheduleShutdownCheck() {
-  base::MessageLoop::current()->PostDelayedTask(
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&ServiceProcess::ShutdownIfNeeded, base::Unretained(this)),
       base::TimeDelta::FromSeconds(kShutdownDelaySeconds));
diff --git a/chrome/service/service_process.h b/chrome/service/service_process.h
index d5942d4..8f2aa4c 100644
--- a/chrome/service/service_process.h
+++ b/chrome/service/service_process.h
@@ -46,17 +46,17 @@ class ServiceProcess : public cloud_print::CloudPrintProxy::Client {
   bool Teardown();
   // TODO(sanjeevr): Change various parts of the code such as
   // net::ProxyService::CreateSystemProxyConfigService to take in
-  // MessageLoopProxy* instead of MessageLoop*. When we have done that, we can
-  // remove the io_thread() and file_thread() accessors and replace them with
-  // io_message_loop_proxy() and file_message_loop_proxy() respectively.
+  // SingleThreadTaskRunner* instead of MessageLoop*. When we have done that,
+  // we can remove the io_thread() and file_thread() accessors and replace them
+  // with io_message_loop_proxy() and file_message_loop_proxy() respectively.
 
   // Returns the thread that we perform I/O coordination on (network requests,
   // communication with renderers, etc.
   // NOTE: You should ONLY use this to pass to IPC or other objects which must
   // need a MessageLoop*. If you just want to post a task, use the thread's
-  // message_loop_proxy() as it takes care of checking that a thread is still
-  // alive, race conditions, lifetime differences etc.
-  // If you still must use this, need to check the return value for NULL.
+  // task_runner() as it takes care of checking that a thread is still alive,
+  // race conditions, lifetime differences etc. If you still must use this,
+  // need to check the return value for NULL.
   base::Thread* io_thread() const {
     return io_thread_.get();
   }
diff --git a/chrome/service/service_process_prefs.cc b/chrome/service/service_process_prefs.cc
index 7f43943..7c69470 100644
--- a/chrome/service/service_process_prefs.cc
+++ b/chrome/service/service_process_prefs.cc
@@ -4,8 +4,8 @@
 
 #include "chrome/service/service_process_prefs.h"
 
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/prefs/pref_filter.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 
 ServiceProcessPrefs::ServiceProcessPrefs(
diff --git a/chrome/service/service_process_prefs_unittest.cc b/chrome/service/service_process_prefs_unittest.cc
index 73284ca..ed5ad04 100644
--- a/chrome/service/service_process_prefs_unittest.cc
+++ b/chrome/service/service_process_prefs_unittest.cc
@@ -18,7 +18,7 @@ class ServiceProcessPrefsTest : public testing::Test {
 
     prefs_.reset(new ServiceProcessPrefs(
         temp_dir_.path().AppendASCII("service_process_prefs.txt"),
-        message_loop_.message_loop_proxy().get()));
+        message_loop_.task_runner().get()));
   }
 
   void TearDown() override { prefs_.reset(); }
diff --git a/chrome/service/service_utility_process_host.cc b/chrome/service/service_utility_process_host.cc
index 765a430..42a5a53 100644
--- a/chrome/service/service_utility_process_host.cc
+++ b/chrome/service/service_utility_process_host.cc
@@ -13,10 +13,10 @@
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/logging.h"
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/metrics/histogram.h"
 #include "base/process/launch.h"
 #include "base/task_runner_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_utility_printing_messages.h"
 #include "content/public/common/child_process_host.h"
@@ -150,9 +150,9 @@ class ServiceUtilityProcessHost::PdfToEmfState {
 
 ServiceUtilityProcessHost::ServiceUtilityProcessHost(
     Client* client,
-    base::MessageLoopProxy* client_message_loop_proxy)
+    base::SingleThreadTaskRunner* client_task_runner)
     : client_(client),
-      client_message_loop_proxy_(client_message_loop_proxy),
+      client_task_runner_(client_task_runner),
       waiting_for_reply_(false),
       weak_ptr_factory_(this) {
   child_process_host_.reset(ChildProcessHost::Create(this));
@@ -258,7 +258,7 @@ void ServiceUtilityProcessHost::OnChildDisconnected() {
   if (waiting_for_reply_) {
     // If we are yet to receive a reply then notify the client that the
     // child died.
-    client_message_loop_proxy_->PostTask(
+    client_task_runner_->PostTask(
         FROM_HERE, base::Bind(&Client::OnChildDied, client_.get()));
     ReportUmaEvent(SERVICE_UTILITY_DISCONNECTED);
     UMA_HISTOGRAM_TIMES("CloudPrint.ServiceUtilityDisconnectTime",
@@ -319,7 +319,7 @@ void ServiceUtilityProcessHost::OnRenderPDFPagesToMetafilesPageDone(
     return OnPDFToEmfFinished(false);
   base::File emf_file = pdf_to_emf_state_->TakeNextFile();
   base::PostTaskAndReplyWithResult(
-      client_message_loop_proxy_.get(), FROM_HERE,
+      client_task_runner_.get(), FROM_HERE,
       base::Bind(&Client::MetafileAvailable, client_.get(), scale_factor,
                  base::Passed(&emf_file)),
       base::Bind(&ServiceUtilityProcessHost::OnMetafileSpooled,
@@ -339,10 +339,9 @@ void ServiceUtilityProcessHost::OnPDFToEmfFinished(bool success) {
     UMA_HISTOGRAM_TIMES("CloudPrint.ServiceUtilityMetafileFailTime",
                         base::Time::Now() - start_time_);
   }
-  client_message_loop_proxy_->PostTask(
-      FROM_HERE,
-      base::Bind(
-          &Client::OnRenderPDFPagesToMetafileDone, client_.get(), success));
+  client_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&Client::OnRenderPDFPagesToMetafileDone,
+                            client_.get(), success));
   pdf_to_emf_state_.reset();
 }
 
@@ -354,10 +353,9 @@ void ServiceUtilityProcessHost::OnGetPrinterCapsAndDefaultsSucceeded(
   UMA_HISTOGRAM_TIMES("CloudPrint.ServiceUtilityCapsTime",
                       base::Time::Now() - start_time_);
   waiting_for_reply_ = false;
-  client_message_loop_proxy_->PostTask(
-      FROM_HERE,
-      base::Bind(&Client::OnGetPrinterCapsAndDefaults, client_.get(), true,
-                 printer_name, caps_and_defaults));
+  client_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&Client::OnGetPrinterCapsAndDefaults, client_.get(),
+                            true, printer_name, caps_and_defaults));
 }
 
 void ServiceUtilityProcessHost::OnGetPrinterSemanticCapsAndDefaultsSucceeded(
@@ -368,7 +366,7 @@ void ServiceUtilityProcessHost::OnGetPrinterSemanticCapsAndDefaultsSucceeded(
   UMA_HISTOGRAM_TIMES("CloudPrint.ServiceUtilitySemanticCapsTime",
                       base::Time::Now() - start_time_);
   waiting_for_reply_ = false;
-  client_message_loop_proxy_->PostTask(
+  client_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&Client::OnGetPrinterSemanticCapsAndDefaults, client_.get(),
                  true, printer_name, caps_and_defaults));
@@ -381,7 +379,7 @@ void ServiceUtilityProcessHost::OnGetPrinterCapsAndDefaultsFailed(
   UMA_HISTOGRAM_TIMES("CloudPrint.ServiceUtilityCapsFailTime",
                       base::Time::Now() - start_time_);
   waiting_for_reply_ = false;
-  client_message_loop_proxy_->PostTask(
+  client_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&Client::OnGetPrinterCapsAndDefaults, client_.get(), false,
                  printer_name, printing::PrinterCapsAndDefaults()));
@@ -394,11 +392,10 @@ void ServiceUtilityProcessHost::OnGetPrinterSemanticCapsAndDefaultsFailed(
   UMA_HISTOGRAM_TIMES("CloudPrint.ServiceUtilitySemanticCapsFailTime",
                       base::Time::Now() - start_time_);
   waiting_for_reply_ = false;
-  client_message_loop_proxy_->PostTask(
-      FROM_HERE,
-      base::Bind(&Client::OnGetPrinterSemanticCapsAndDefaults,
-                 client_.get(), false, printer_name,
-                 printing::PrinterSemanticCapsAndDefaults()));
+  client_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&Client::OnGetPrinterSemanticCapsAndDefaults,
+                            client_.get(), false, printer_name,
+                            printing::PrinterSemanticCapsAndDefaults()));
 }
 
 bool ServiceUtilityProcessHost::Client::MetafileAvailable(float scale_factor,
diff --git a/chrome/service/service_utility_process_host.h b/chrome/service/service_utility_process_host.h
index a69c7ac..18b561e 100644
--- a/chrome/service/service_utility_process_host.h
+++ b/chrome/service/service_utility_process_host.h
@@ -17,7 +17,6 @@ namespace base {
 class CommandLine;
 class File;
 class FilePath;
-class MessageLoopProxy;
 class ScopedTempDir;
 }  // namespace base
 
@@ -84,7 +83,7 @@ class ServiceUtilityProcessHost : public content::ChildProcessHostDelegate {
   };
 
   ServiceUtilityProcessHost(Client* client,
-                            base::MessageLoopProxy* client_message_loop_proxy);
+                            base::SingleThreadTaskRunner* client_task_runner);
   ~ServiceUtilityProcessHost() override;
 
   // Starts a process to render the specified pages in the given PDF file into
@@ -146,7 +145,7 @@ class ServiceUtilityProcessHost : public content::ChildProcessHostDelegate {
   base::Process process_;
   // A pointer to our client interface, who will be informed of progress.
   scoped_refptr<Client> client_;
-  scoped_refptr<base::MessageLoopProxy> client_message_loop_proxy_;
+  scoped_refptr<base::SingleThreadTaskRunner> client_task_runner_;
   bool waiting_for_reply_;
 
   // Start time of operation.
diff --git a/chrome/test/base/browser_with_test_window_test.cc b/chrome/test/base/browser_with_test_window_test.cc
index 245c9b9..b9e4203 100644
--- a/chrome/test/base/browser_with_test_window_test.cc
+++ b/chrome/test/base/browser_with_test_window_test.cc
@@ -4,7 +4,10 @@
 
 #include "chrome/test/base/browser_with_test_window_test.h"
 
+#include "base/location.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/browser/profiles/profile_destroyer.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_navigator.h"
@@ -117,8 +120,8 @@ void BrowserWithTestWindowTest::TearDown() {
 
   // A Task is leaked if we don't destroy everything, then run the message
   // loop.
-  base::MessageLoop::current()->PostTask(FROM_HERE,
-                                         base::MessageLoop::QuitClosure());
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::MessageLoop::QuitClosure());
   base::MessageLoop::current()->Run();
 
 #if defined(TOOLKIT_VIEWS)
diff --git a/chrome/test/base/in_process_browser_test.cc b/chrome/test/base/in_process_browser_test.cc
index 8c09bcc..cb63fb1 100644
--- a/chrome/test/base/in_process_browser_test.cc
+++ b/chrome/test/base/in_process_browser_test.cc
@@ -11,9 +11,12 @@
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/lazy_instance.h"
+#include "base/location.h"
 #include "base/path_service.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/test/test_file_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/threading/non_thread_safe.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
@@ -576,8 +579,8 @@ void InProcessBrowserTest::QuitBrowsers() {
   // Invoke AttemptExit on a running message loop.
   // AttemptExit exits the message loop after everything has been
   // shut down properly.
-  base::MessageLoopForUI::current()->PostTask(FROM_HERE,
-                                              base::Bind(&chrome::AttemptExit));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::Bind(&chrome::AttemptExit));
   content::RunMessageLoop();
 
 #if defined(OS_MACOSX)
diff --git a/chrome/test/base/testing_io_thread_state.cc b/chrome/test/base/testing_io_thread_state.cc
index 30b9069..8ebd202 100644
--- a/chrome/test/base/testing_io_thread_state.cc
+++ b/chrome/test/base/testing_io_thread_state.cc
@@ -4,8 +4,10 @@
 
 #include "chrome/test/base/testing_io_thread_state.h"
 
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/location.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/time/tick_clock.h"
 #include "chrome/browser/io_thread.h"
 #include "chrome/test/base/testing_browser_process.h"
@@ -26,9 +28,8 @@ base::Closure ThreadSafeQuit(base::RunLoop* run_loop) {
   } else {
     using base::Bind;
     using base::IgnoreResult;
-    return Bind(IgnoreResult(&base::MessageLoopProxy::PostTask),
-                base::MessageLoopProxy::current(),
-                FROM_HERE,
+    return Bind(IgnoreResult(&base::SingleThreadTaskRunner::PostTask),
+                base::ThreadTaskRunnerHandle::Get(), FROM_HERE,
                 run_loop->QuitClosure());
   }
 }
diff --git a/chrome/test/base/testing_profile.cc b/chrome/test/base/testing_profile.cc
index 0497fbd..32da645 100644
--- a/chrome/test/base/testing_profile.cc
+++ b/chrome/test/base/testing_profile.cc
@@ -7,11 +7,13 @@
 #include "base/base_paths.h"
 #include "base/command_line.h"
 #include "base/files/file_util.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/location.h"
 #include "base/path_service.h"
 #include "base/prefs/testing_pref_store.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/browser/autocomplete/autocomplete_classifier.h"
 #include "chrome/browser/autocomplete/in_memory_url_index.h"
 #include "chrome/browser/autocomplete/in_memory_url_index_factory.h"
@@ -319,7 +321,7 @@ TestingProfile::TestingProfile(const base::FilePath& path,
       delegate_(delegate) {
   Init();
   if (delegate_) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::Bind(&TestingProfile::FinishInit, base::Unretained(this)));
   } else {
@@ -376,7 +378,7 @@ TestingProfile::TestingProfile(
   // TODO(atwilson): See if this is still required once we convert the current
   // users of the constructor that takes a Delegate* param.
   if (delegate_) {
-    base::MessageLoop::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::Bind(&TestingProfile::FinishInit, base::Unretained(this)));
   } else {
@@ -596,8 +598,8 @@ void TestingProfile::DestroyHistoryService() {
 
   // Make sure we don't have any event pending that could disrupt the next
   // test.
-  base::MessageLoop::current()->PostTask(FROM_HERE,
-                                         base::MessageLoop::QuitClosure());
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE, base::MessageLoop::QuitClosure());
   base::MessageLoop::current()->Run();
 }
 
@@ -654,7 +656,7 @@ scoped_ptr<content::ZoomLevelDelegate> TestingProfile::CreateZoomLevelDelegate(
 }
 
 scoped_refptr<base::SequencedTaskRunner> TestingProfile::GetIOTaskRunner() {
-  return base::MessageLoop::current()->message_loop_proxy();
+  return base::MessageLoop::current()->task_runner();
 }
 
 TestingPrefServiceSyncable* TestingProfile::GetTestingPrefService() {
diff --git a/chrome/test/base/tracing_browsertest.cc b/chrome/test/base/tracing_browsertest.cc
index e6128a3..3ebc610 100644
--- a/chrome/test/base/tracing_browsertest.cc
+++ b/chrome/test/base/tracing_browsertest.cc
@@ -4,8 +4,10 @@
 
 #include "chrome/test/base/tracing.h"
 
-#include "base/message_loop/message_loop.h"
+#include "base/location.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/trace_event/trace_event.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
@@ -56,7 +58,8 @@ IN_PROC_BROWSER_TEST_F(TracingBrowserTest, BeginTracingWithWatch) {
 
   // One event after wait.
   ASSERT_TRUE(BeginTracingWithWatch(g_category, g_category, g_event, 1));
-  base::MessageLoop::current()->PostTask(FROM_HERE, base::Bind(&AddEvents, 1));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
+                                                base::Bind(&AddEvents, 1));
   EXPECT_TRUE(WaitForWatchEvent(no_timeout));
   ASSERT_TRUE(EndTracing(&json_events));
 
@@ -74,7 +77,8 @@ IN_PROC_BROWSER_TEST_F(TracingBrowserTest, BeginTracingWithWatch) {
 
   // Multi event after wait.
   ASSERT_TRUE(BeginTracingWithWatch(g_category, g_category, g_event, 5));
-  base::MessageLoop::current()->PostTask(FROM_HERE, base::Bind(&AddEvents, 5));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
+                                                base::Bind(&AddEvents, 5));
   EXPECT_TRUE(WaitForWatchEvent(no_timeout));
   ASSERT_TRUE(EndTracing(&json_events));
 
diff --git a/chrome/test/base/view_event_test_base.cc b/chrome/test/base/view_event_test_base.cc
index 34c6eda..1262582 100644
--- a/chrome/test/base/view_event_test_base.cc
+++ b/chrome/test/base/view_event_test_base.cc
@@ -5,7 +5,9 @@
 #include "chrome/test/base/view_event_test_base.h"
 
 #include "base/bind.h"
-#include "base/message_loop/message_loop.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/test/base/chrome_unit_test_suite.h"
 #include "chrome/test/base/interactive_test_utils.h"
 #include "chrome/test/base/testing_browser_process.h"
@@ -135,7 +137,7 @@ void ViewEventTestBase::StartMessageLoopAndRunTest() {
 
   // Schedule a task that starts the test. Need to do this as we're going to
   // run the message loop.
-  base::MessageLoop::current()->PostTask(
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&ViewEventTestBase::DoTestOnMessageLoop, this));
 
   content::RunThisRunLoop(&run_loop_);
@@ -150,7 +152,7 @@ void ViewEventTestBase::ScheduleMouseMoveInBackground(int x, int y) {
     dnd_thread_.reset(new base::Thread("mouse-move-thread"));
     dnd_thread_->Start();
   }
-  dnd_thread_->message_loop()->PostDelayedTask(
+  dnd_thread_->task_runner()->PostDelayedTask(
       FROM_HERE,
       base::Bind(base::IgnoreResult(&ui_controls::SendMouseMove), x, y),
       base::TimeDelta::FromMilliseconds(kMouseMoveDelayMS));
diff --git a/chrome/test/chromedriver/chrome/adb_impl.h b/chrome/test/chromedriver/chrome/adb_impl.h
index 895bd78..5f82dd3 100644
--- a/chrome/test/chromedriver/chrome/adb_impl.h
+++ b/chrome/test/chromedriver/chrome/adb_impl.h
@@ -21,7 +21,7 @@ class Status;
 class AdbImpl : public Adb {
  public:
   explicit AdbImpl(
-      const scoped_refptr<base::SingleThreadTaskRunner>& io_message_loop_proxy,
+      const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
       int port);
   ~AdbImpl() override;
 
diff --git a/chrome/test/chromedriver/commands.cc b/chrome/test/chromedriver/commands.cc
index 2a9b794..667d5e9 100644
--- a/chrome/test/chromedriver/commands.cc
+++ b/chrome/test/chromedriver/commands.cc
@@ -10,13 +10,15 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/linked_ptr.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/sys_info.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/test/chromedriver/capabilities.h"
 #include "chrome/test/chromedriver/chrome/browser_info.h"
@@ -65,7 +67,7 @@ void ExecuteCreateSession(
     return;
   }
 
-  thread->message_loop()->PostTask(
+  thread->task_runner()->PostTask(
       FROM_HERE, base::Bind(&SetThreadLocalSession, base::Passed(&session)));
   session_thread_map
       ->insert(std::make_pair(new_id, make_linked_ptr(thread.release())));
@@ -126,10 +128,8 @@ void ExecuteGetSessions(const Command& session_capabilities_command,
                                                run_loop.QuitClosure(),
                                                session_list.get()));
   }
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      run_loop.QuitClosure(),
-      base::TimeDelta::FromSeconds(10));
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, run_loop.QuitClosure(), base::TimeDelta::FromSeconds(10));
   base::MessageLoop::current()->SetNestableTasksAllowed(true);
   run_loop.Run();
 
@@ -176,7 +176,7 @@ void ExecuteQuitAll(
                                 weak_ptr_factory.GetWeakPtr(),
                                 run_loop.QuitClosure()));
   }
-  base::MessageLoop::current()->PostDelayedTask(
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
       FROM_HERE, run_loop.QuitClosure(), base::TimeDelta::FromSeconds(10));
   // Uses a nested run loop to block this thread until all the quit
   // commands have executed, or the timeout expires.
@@ -303,18 +303,13 @@ void ExecuteSessionCommand(
     Status status(return_ok_without_session ? kOk : kNoSuchSession);
     callback.Run(status, scoped_ptr<base::Value>(), session_id);
   } else {
-    iter->second->message_loop()
-        ->PostTask(FROM_HERE,
-                   base::Bind(&ExecuteSessionCommandOnSessionThread,
-                              command_name,
-                              command,
-                              return_ok_without_session,
+    iter->second->task_runner()->PostTask(
+        FROM_HERE, base::Bind(&ExecuteSessionCommandOnSessionThread,
+                              command_name, command, return_ok_without_session,
                               base::Passed(make_scoped_ptr(params.DeepCopy())),
-                              base::MessageLoopProxy::current(),
-                              callback,
+                              base::ThreadTaskRunnerHandle::Get(), callback,
                               base::Bind(&TerminateSessionThreadOnCommandThread,
-                                         session_thread_map,
-                                         session_id)));
+                                         session_thread_map, session_id)));
   }
 }
 
diff --git a/chrome/test/chromedriver/commands_unittest.cc b/chrome/test/chromedriver/commands_unittest.cc
index b5320c2..a0e0a5e 100644
--- a/chrome/test/chromedriver/commands_unittest.cc
+++ b/chrome/test/chromedriver/commands_unittest.cc
@@ -8,9 +8,10 @@
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
+#include "base/location.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread.h"
 #include "base/values.h"
@@ -218,7 +219,7 @@ TEST(CommandsTest, ExecuteSessionCommand) {
   linked_ptr<base::Thread> thread(new base::Thread("1"));
   ASSERT_TRUE(thread->Start());
   std::string id("id");
-  thread->message_loop()->PostTask(
+  thread->task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&internal::CreateSessionOnSessionThreadForTesting, id));
   map[id] = thread;
@@ -700,7 +701,7 @@ TEST(CommandsTest, SuccessNotifyingCommandListeners) {
   linked_ptr<base::Thread> thread(new base::Thread("1"));
   ASSERT_TRUE(thread->Start());
   std::string id("id");
-  thread->message_loop()->PostTask(
+  thread->task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&internal::CreateSessionOnSessionThreadForTesting, id));
 
@@ -789,7 +790,7 @@ TEST(CommandsTest, ErrorNotifyingCommandListeners) {
   linked_ptr<base::Thread> thread(new base::Thread("1"));
   ASSERT_TRUE(thread->Start());
   std::string id("id");
-  thread->message_loop()->PostTask(
+  thread->task_runner()->PostTask(
       FROM_HERE,
       base::Bind(&internal::CreateSessionOnSessionThreadForTesting, id));
   map[id] = thread;
@@ -798,9 +799,8 @@ TEST(CommandsTest, ErrorNotifyingCommandListeners) {
   // was called before (as opposed to after) command execution. We don't need to
   // verify this again, so we can just add |listener| with PostTask.
   CommandListener* listener = new FailingCommandListener();
-  thread->message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(&AddListenerToSessionIfSessionExists, listener));
+  thread->task_runner()->PostTask(
+      FROM_HERE, base::Bind(&AddListenerToSessionIfSessionExists, listener));
 
   base::DictionaryValue params;
   // The command should never be executed if BeforeCommand fails for a listener.
@@ -818,7 +818,6 @@ TEST(CommandsTest, ErrorNotifyingCommandListeners) {
       base::Bind(&OnFailBecauseErrorNotifyingListeners, &run_loop));
   run_loop.Run();
 
-  thread->message_loop()->PostTask(
-      FROM_HERE,
-      base::Bind(&VerifySessionWasDeleted));
+  thread->task_runner()->PostTask(FROM_HERE,
+                                  base::Bind(&VerifySessionWasDeleted));
 }
diff --git a/chrome/test/chromedriver/net/net_util_unittest.cc b/chrome/test/chromedriver/net/net_util_unittest.cc
index f0c3534..b976373 100644
--- a/chrome/test/chromedriver/net/net_util_unittest.cc
+++ b/chrome/test/chromedriver/net/net_util_unittest.cc
@@ -9,7 +9,6 @@
 #include "base/location.h"
 #include "base/memory/ref_counted.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/synchronization/waitable_event.h"
@@ -34,22 +33,19 @@ class FetchUrlTest : public testing::Test,
         response_(kSendHello) {
     base::Thread::Options options(base::MessageLoop::TYPE_IO, 0);
     CHECK(io_thread_.StartWithOptions(options));
-    context_getter_ = new URLRequestContextGetter(
-        io_thread_.message_loop_proxy());
+    context_getter_ = new URLRequestContextGetter(io_thread_.task_runner());
     base::WaitableEvent event(false, false);
-    io_thread_.message_loop_proxy()->PostTask(
+    io_thread_.task_runner()->PostTask(
         FROM_HERE,
-        base::Bind(&FetchUrlTest::InitOnIO,
-                   base::Unretained(this), &event));
+        base::Bind(&FetchUrlTest::InitOnIO, base::Unretained(this), &event));
     event.Wait();
   }
 
   ~FetchUrlTest() override {
     base::WaitableEvent event(false, false);
-    io_thread_.message_loop_proxy()->PostTask(
-        FROM_HERE,
-        base::Bind(&FetchUrlTest::DestroyServerOnIO,
-                   base::Unretained(this), &event));
+    io_thread_.task_runner()->PostTask(
+        FROM_HERE, base::Bind(&FetchUrlTest::DestroyServerOnIO,
+                              base::Unretained(this), &event));
     event.Wait();
   }
 
diff --git a/chrome/test/chromedriver/net/port_server_unittest.cc b/chrome/test/chromedriver/net/port_server_unittest.cc
index c9b88c8..d711710 100644
--- a/chrome/test/chromedriver/net/port_server_unittest.cc
+++ b/chrome/test/chromedriver/net/port_server_unittest.cc
@@ -7,7 +7,7 @@
 #include "base/bind.h"
 #include "base/guid.h"
 #include "base/location.h"
-#include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "base/sync_socket.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/thread.h"
@@ -124,10 +124,9 @@ class PortServerTest : public testing::Test {
                  const std::string& response,
                  std::string* request) {
     base::WaitableEvent listen_event(false, false);
-    thread_.message_loop()->PostTask(
+    thread_.task_runner()->PostTask(
         FROM_HERE,
-        base::Bind(
-            &RunServerOnThread, path, response, &listen_event, request));
+        base::Bind(&RunServerOnThread, path, response, &listen_event, request));
     ASSERT_TRUE(listen_event.TimedWait(base::TimeDelta::FromSeconds(5)));
   }
 
diff --git a/chrome/test/chromedriver/net/sync_websocket_impl_unittest.cc b/chrome/test/chromedriver/net/sync_websocket_impl_unittest.cc
index 28b808a..b7d27b5 100644
--- a/chrome/test/chromedriver/net/sync_websocket_impl_unittest.cc
+++ b/chrome/test/chromedriver/net/sync_websocket_impl_unittest.cc
@@ -7,7 +7,6 @@
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/platform_thread.h"
 #include "base/threading/thread.h"
@@ -30,8 +29,7 @@ class SyncWebSocketImplTest : public testing::Test {
   void SetUp() override {
     base::Thread::Options options(base::MessageLoop::TYPE_IO, 0);
     ASSERT_TRUE(client_thread_.StartWithOptions(options));
-    context_getter_ = new URLRequestContextGetter(
-        client_thread_.message_loop_proxy());
+    context_getter_ = new URLRequestContextGetter(client_thread_.task_runner());
     ASSERT_TRUE(server_.Start());
   }
 
diff --git a/chrome/test/chromedriver/net/test_http_server.cc b/chrome/test/chromedriver/net/test_http_server.cc
index 6b8a4bc..a3d8e38 100644
--- a/chrome/test/chromedriver/net/test_http_server.cc
+++ b/chrome/test/chromedriver/net/test_http_server.cc
@@ -7,7 +7,7 @@
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/time/time.h"
 #include "net/base/ip_endpoint.h"
@@ -36,10 +36,9 @@ bool TestHttpServer::Start() {
     return false;
   bool success;
   base::WaitableEvent event(false, false);
-  thread_.message_loop_proxy()->PostTask(
-      FROM_HERE,
-      base::Bind(&TestHttpServer::StartOnServerThread,
-                 base::Unretained(this), &success, &event));
+  thread_.task_runner()->PostTask(
+      FROM_HERE, base::Bind(&TestHttpServer::StartOnServerThread,
+                            base::Unretained(this), &success, &event));
   event.Wait();
   return success;
 }
@@ -48,10 +47,9 @@ void TestHttpServer::Stop() {
   if (!thread_.IsRunning())
     return;
   base::WaitableEvent event(false, false);
-  thread_.message_loop_proxy()->PostTask(
-      FROM_HERE,
-      base::Bind(&TestHttpServer::StopOnServerThread,
-                 base::Unretained(this), &event));
+  thread_.task_runner()->PostTask(
+      FROM_HERE, base::Bind(&TestHttpServer::StopOnServerThread,
+                            base::Unretained(this), &event));
   event.Wait();
   thread_.Stop();
 }
diff --git a/chrome/test/chromedriver/net/websocket_unittest.cc b/chrome/test/chromedriver/net/websocket_unittest.cc
index 835b240..2922c7f 100644
--- a/chrome/test/chromedriver/net/websocket_unittest.cc
+++ b/chrome/test/chromedriver/net/websocket_unittest.cc
@@ -11,7 +11,6 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread.h"
@@ -31,7 +30,7 @@ void OnConnectFinished(base::RunLoop* run_loop, int* save_error, int error) {
 
 void RunPending(base::MessageLoop* loop) {
   base::RunLoop run_loop;
-  loop->PostTask(FROM_HERE, run_loop.QuitClosure());
+  loop->task_runner()->PostTask(FROM_HERE, run_loop.QuitClosure());
   run_loop.Run();
 }
 
@@ -92,9 +91,8 @@ class WebSocketTest : public testing::Test {
     scoped_ptr<WebSocket> sock(new WebSocket(url, listener));
     base::RunLoop run_loop;
     sock->Connect(base::Bind(&OnConnectFinished, &run_loop, &error));
-    loop_.PostDelayedTask(
-        FROM_HERE, run_loop.QuitClosure(),
-        base::TimeDelta::FromSeconds(10));
+    loop_.task_runner()->PostDelayedTask(FROM_HERE, run_loop.QuitClosure(),
+                                         base::TimeDelta::FromSeconds(10));
     run_loop.Run();
     if (error == net::OK)
       return sock.Pass();
@@ -113,9 +111,8 @@ class WebSocketTest : public testing::Test {
       ASSERT_TRUE(sock->Send(messages[i]));
     }
     base::RunLoop run_loop;
-    loop_.PostDelayedTask(
-        FROM_HERE, run_loop.QuitClosure(),
-        base::TimeDelta::FromSeconds(10));
+    loop_.task_runner()->PostDelayedTask(FROM_HERE, run_loop.QuitClosure(),
+                                         base::TimeDelta::FromSeconds(10));
     run_loop.Run();
   }
 
@@ -163,9 +160,8 @@ TEST_F(WebSocketTest, CloseOnReceive) {
   scoped_ptr<WebSocket> sock(CreateConnectedWebSocket(&listener));
   ASSERT_TRUE(sock);
   ASSERT_TRUE(sock->Send("hi"));
-  loop_.PostDelayedTask(
-      FROM_HERE, run_loop.QuitClosure(),
-      base::TimeDelta::FromSeconds(10));
+  loop_.task_runner()->PostDelayedTask(FROM_HERE, run_loop.QuitClosure(),
+                                       base::TimeDelta::FromSeconds(10));
   run_loop.Run();
 }
 
@@ -177,9 +173,8 @@ TEST_F(WebSocketTest, CloseOnSend) {
   server_.Stop();
 
   sock->Send("hi");
-  loop_.PostDelayedTask(
-      FROM_HERE, run_loop.QuitClosure(),
-      base::TimeDelta::FromSeconds(10));
+  loop_.task_runner()->PostDelayedTask(FROM_HERE, run_loop.QuitClosure(),
+                                       base::TimeDelta::FromSeconds(10));
   run_loop.Run();
   ASSERT_FALSE(sock->Send("hi"));
 }
diff --git a/chrome/test/chromedriver/server/chromedriver_server.cc b/chrome/test/chromedriver/server/chromedriver_server.cc
index 2d73020..4782eb6 100644
--- a/chrome/test/chromedriver/server/chromedriver_server.cc
+++ b/chrome/test/chromedriver/server/chromedriver_server.cc
@@ -22,6 +22,7 @@
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/threading/thread.h"
 #include "base/threading/thread_local.h"
 #include "chrome/test/chromedriver/logging.h"
@@ -136,12 +137,10 @@ void HandleRequestOnIOThread(
     const net::HttpServerRequestInfo& request,
     const HttpResponseSenderFunc& send_response_func) {
   cmd_task_runner->PostTask(
-      FROM_HERE,
-      base::Bind(handle_request_on_cmd_func,
-                 request,
-                 base::Bind(&SendResponseOnCmdThread,
-                            base::MessageLoopProxy::current(),
-                            send_response_func)));
+      FROM_HERE, base::Bind(handle_request_on_cmd_func, request,
+                            base::Bind(&SendResponseOnCmdThread,
+                                       base::ThreadTaskRunnerHandle::Get(),
+                                       send_response_func)));
 }
 
 base::LazyInstance<base::ThreadLocalPointer<HttpServer> >
@@ -177,22 +176,16 @@ void RunServer(uint16 port,
 
   base::MessageLoop cmd_loop;
   base::RunLoop cmd_run_loop;
-  HttpHandler handler(cmd_run_loop.QuitClosure(),
-                      io_thread.message_loop_proxy(),
-                      url_base,
-                      adb_port,
-                      port_server.Pass());
+  HttpHandler handler(cmd_run_loop.QuitClosure(), io_thread.task_runner(),
+                      url_base, adb_port, port_server.Pass());
   HttpRequestHandlerFunc handle_request_func =
       base::Bind(&HandleRequestOnCmdThread, &handler, whitelisted_ips);
 
-  io_thread.message_loop()
-      ->PostTask(FROM_HERE,
-                 base::Bind(&StartServerOnIOThread,
-                            port,
-                            allow_remote,
-                            base::Bind(&HandleRequestOnIOThread,
-                                       cmd_loop.message_loop_proxy(),
-                                       handle_request_func)));
+  io_thread.message_loop()->PostTask(
+      FROM_HERE,
+      base::Bind(&StartServerOnIOThread, port, allow_remote,
+                 base::Bind(&HandleRequestOnIOThread, cmd_loop.task_runner(),
+                            handle_request_func)));
   // Run the command loop. This loop is quit after the response for a shutdown
   // request is posted to the IO loop. After the command loop quits, a task
   // is posted to the IO loop to stop the server. Lastly, the IO thread is
diff --git a/chrome/test/chromedriver/server/http_handler.cc b/chrome/test/chromedriver/server/http_handler.cc
index 78b2cc0a..32cb7e6 100644
--- a/chrome/test/chromedriver/server/http_handler.cc
+++ b/chrome/test/chromedriver/server/http_handler.cc
@@ -11,11 +11,11 @@
 #include "base/logging.h"  // For CHECK macros.
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/sys_info.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/test/chromedriver/alert_commands.h"
 #include "chrome/test/chromedriver/chrome/adb_impl.h"
diff --git a/chrome/test/chromedriver/session_commands.cc b/chrome/test/chromedriver/session_commands.cc
index 5c56d82..99f5f02 100644
--- a/chrome/test/chromedriver/session_commands.cc
+++ b/chrome/test/chromedriver/session_commands.cc
@@ -11,9 +11,9 @@
 #include "base/files/file_util.h"
 #include "base/logging.h"  // For CHECK macros.
 #include "base/memory/ref_counted.h"
-#include "base/message_loop/message_loop_proxy.h"
 #include "base/synchronization/lock.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "chrome/test/chromedriver/basic_types.h"
 #include "chrome/test/chromedriver/capabilities.h"
diff --git a/chrome/test/ppapi/ppapi_test.cc b/chrome/test/ppapi/ppapi_test.cc
index 48d758a..6e9fc03 100644
--- a/chrome/test/ppapi/ppapi_test.cc
+++ b/chrome/test/ppapi/ppapi_test.cc
@@ -6,9 +6,12 @@
 
 #include "base/command_line.h"
 #include "base/files/file_util.h"
+#include "base/location.h"
 #include "base/path_service.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/infobars/infobar_service.h"
 #include "chrome/browser/profiles/profile.h"
@@ -93,9 +96,9 @@ void PPAPITestBase::InfoBarObserver::Observe(
   // It's not safe to remove the infobar here, since other observers (e.g. the
   // InfoBarContainer) may still need to access it.  Instead, post a task to
   // do all necessary infobar manipulation as soon as this call stack returns.
-  base::MessageLoop::current()->PostTask(
-      FROM_HERE, base::Bind(&InfoBarObserver::VerifyInfoBarState,
-                            base::Unretained(this)));
+  base::ThreadTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE,
+      base::Bind(&InfoBarObserver::VerifyInfoBarState, base::Unretained(this)));
 }
 
 void PPAPITestBase::InfoBarObserver::VerifyInfoBarState() {
diff --git a/chrome/utility/font_cache_handler_win.cc b/chrome/utility/font_cache_handler_win.cc
index cd7aa70..cf850c0 100644
--- a/chrome/utility/font_cache_handler_win.cc
+++ b/chrome/utility/font_cache_handler_win.cc
@@ -29,7 +29,7 @@ bool FontCacheHandler::OnMessageReceived(const IPC::Message& message) {
 void FontCacheHandler::OnBuildFontCache(const base::FilePath& full_path) {
   DCHECK(!cache_thread_);
 
-  utility_task_runner_ = base::MessageLoop::current()->message_loop_proxy();
+  utility_task_runner_ = base::MessageLoop::current()->task_runner();
 
   // Create worker thread for building font cache.
   cache_thread_.reset(new base::Thread("font_cache_thread"));
diff --git a/chrome/utility/image_writer/image_writer.cc b/chrome/utility/image_writer/image_writer.cc
index 2a2b8a1..1df1513 100644
--- a/chrome/utility/image_writer/image_writer.cc
+++ b/chrome/utility/image_writer/image_writer.cc
@@ -4,7 +4,10 @@
 
 #include "chrome/utility/image_writer/image_writer.h"
 
+#include "base/location.h"
 #include "base/memory/aligned_memory.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "chrome/utility/image_writer/error_messages.h"
 #include "chrome/utility/image_writer/image_writer_handler.h"
 #include "content/public/utility/utility_thread.h"
@@ -69,7 +72,7 @@ const base::FilePath& ImageWriter::GetImagePath() { return image_path_; }
 const base::FilePath& ImageWriter::GetDevicePath() { return device_path_; }
 
 void ImageWriter::PostTask(const base::Closure& task) {
-  base::MessageLoop::current()->PostTask(FROM_HERE, task);
+  base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, task);
 }
 
 void ImageWriter::PostProgress(int64 progress) {
diff --git a/chrome/utility/local_discovery/service_discovery_message_handler.cc b/chrome/utility/local_discovery/service_discovery_message_handler.cc
index 3110c94..429257a 100644
--- a/chrome/utility/local_discovery/service_discovery_message_handler.cc
+++ b/chrome/utility/local_discovery/service_discovery_message_handler.cc
@@ -7,6 +7,8 @@
 #include <algorithm>
 
 #include "base/lazy_instance.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
 #include "chrome/common/local_discovery/local_discovery_messages.h"
 #include "chrome/common/local_discovery/service_discovery_client_impl.h"
 #include "content/public/utility/utility_thread.h"
@@ -202,11 +204,11 @@ bool ServiceDiscoveryMessageHandler::InitializeThread() {
     return true;
   if (discovery_thread_)
     return false;
-  utility_task_runner_ = base::MessageLoop::current()->message_loop_proxy();
+  utility_task_runner_ = base::MessageLoop::current()->task_runner();
   discovery_thread_.reset(new base::Thread("ServiceDiscoveryThread"));
   base::Thread::Options thread_options(base::MessageLoop::TYPE_IO, 0);
   if (discovery_thread_->StartWithOptions(thread_options)) {
-    discovery_task_runner_ = discovery_thread_->message_loop_proxy();
+    discovery_task_runner_ = discovery_thread_->task_runner();
     discovery_task_runner_->PostTask(FROM_HERE,
         base::Bind(&ServiceDiscoveryMessageHandler::InitializeMdns,
                     base::Unretained(this)));
diff --git a/chrome/utility/media_galleries/media_metadata_parser.cc b/chrome/utility/media_galleries/media_metadata_parser.cc
index dbce009..c5da99e 100644
--- a/chrome/utility/media_galleries/media_metadata_parser.cc
+++ b/chrome/utility/media_galleries/media_metadata_parser.cc
@@ -7,8 +7,8 @@
 #include <string>
 
 #include "base/bind.h"
+#include "base/location.h"
 #include "base/memory/linked_ptr.h"
-#include "base/message_loop/message_loop.h"
 #include "base/strings/string_util.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread.h"
@@ -175,10 +175,9 @@ void MediaMetadataParser::Start(const MetadataCallback& callback) {
 
     media_thread_.reset(new base::Thread("media_thread"));
     CHECK(media_thread_->Start());
-    media_thread_->message_loop_proxy()->PostTaskAndReply(
-        FROM_HERE,
-        base::Bind(&ParseAudioVideoMetadata, source_, get_attached_images_,
-                   metadata, attached_images),
+    media_thread_->task_runner()->PostTaskAndReply(
+        FROM_HERE, base::Bind(&ParseAudioVideoMetadata, source_,
+                              get_attached_images_, metadata, attached_images),
         base::Bind(&FinishParseAudioVideoMetadata, callback,
                    base::Owned(metadata), base::Owned(attached_images)));
     return;
diff --git a/chrome/utility/profile_import_handler.cc b/chrome/utility/profile_import_handler.cc
index 30941e5..62ad739 100644
--- a/chrome/utility/profile_import_handler.cc
+++ b/chrome/utility/profile_import_handler.cc
@@ -5,7 +5,9 @@
 #include "chrome/utility/profile_import_handler.h"
 
 #include "base/bind.h"
+#include "base/location.h"
 #include "base/memory/ref_counted.h"
+#include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/threading/thread.h"
 #include "chrome/common/importer/profile_import_process_messages.h"
@@ -64,7 +66,7 @@ void ProfileImportHandler::OnImportStart(
     NOTREACHED();
     ImporterCleanup();
   }
-  import_thread_->message_loop()->PostTask(
+  import_thread_->task_runner()->PostTask(
       FROM_HERE, base::Bind(&Importer::StartImport, importer_.get(),
                             source_profile, items, bridge_));
 }