Remove all remaining traces of MessageLoopProxy.

chrome/browser/chrome_device_client.cc

Index: chrome/browser/chrome_device_client.cc
diff --git a/chrome/browser/chrome_device_client.cc b/chrome/browser/chrome_device_client.cc
index 93d17ffbbf6eab4590abef7efbd08e9bcd2220fb..7ce9c4fe5535beabc8b9500ef2fadbf168c5fee2 100644
--- a/chrome/browser/chrome_device_client.cc
+++ b/chrome/browser/chrome_device_client.cc
@@ -20,7 +20,7 @@ device::UsbService* ChromeDeviceClient::GetUsbService() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   if (!usb_service_) {
     usb_service_ = device::UsbService::Create(
-        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE));
+        BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE));
   }
   return usb_service_.get();
 }
@@ -30,7 +30,7 @@ device::HidService* ChromeDeviceClient::GetHidService() {
 #if !defined(OS_ANDROID)
   if (!hid_service_) {
     hid_service_ = device::HidService::Create(
-        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE));
+        BrowserThread::GetTaskRunnerForThread(BrowserThread::FILE));
   }
 #endif
   return hid_service_.get();