Replace MessageLoopProxy usage with ThreadTaskRunnerHandle in components/storage_monitor module.

MessageLoopProxy is deprecated.
This basically does a search and replace:

MessageLoopProxy::current() -> ThreadTaskRunnerHandle::Get().

BUG=391045

Review URL: https://codereview.chromium.org/1126963003

Cr-Commit-Position: refs/heads/master@{#330720}

components/storage_monitor/storage_monitor_chromeos.cc

@@ -6,6 +6,7 @@
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
+#include "base/single_thread_task_runner.h"
 #include "base/stl_util.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
@@ -104,9 +105,9 @@ void StorageMonitorCros::Init() {
   CheckExistingMountPoints();
 
   if (!media_transfer_protocol_manager_) {
-    scoped_refptr<base::MessageLoopProxy> loop_proxy;
     media_transfer_protocol_manager_.reset(
-        device::MediaTransferProtocolManager::Initialize(loop_proxy));
+        device::MediaTransferProtocolManager::Initialize(
+                    scoped_refptr<base::SingleThreadTaskRunner>()));
   }
 
   media_transfer_protocol_device_observer_.reset(

components/storage_monitor/storage_monitor_linux.cc

@@ -263,10 +263,9 @@ void StorageMonitorLinux::Init() {
                  weak_ptr_factory_.GetWeakPtr()));
 
   if (!media_transfer_protocol_manager_) {
-    scoped_refptr<base::MessageLoopProxy> loop_proxy =
-        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE);
     media_transfer_protocol_manager_.reset(
-        device::MediaTransferProtocolManager::Initialize(loop_proxy));
+        device::MediaTransferProtocolManager::Initialize(
+            BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE)));
   }
 
   media_transfer_protocol_device_observer_.reset(

components/storage_monitor/storage_monitor_linux_unittest.cc

@@ -17,6 +17,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
 #include "components/storage_monitor/mock_removable_storage_observer.h"
 #include "components/storage_monitor/removable_device_constants.h"
 #include "components/storage_monitor/storage_info.h"
@@ -132,7 +133,7 @@ class TestStorageMonitorLinux : public StorageMonitorLinux {
   void UpdateMtab(
       const MtabWatcherLinux::MountPointDeviceMap& new_mtab) override {
     StorageMonitorLinux::UpdateMtab(new_mtab);
-    base::MessageLoopProxy::current()->PostTask(
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::MessageLoop::QuitClosure());
   }