Migrate HidServiceLinux and HidConnectionLinux to BrowserThread::UI.

device/hid/hid_connection_unittest.cc

Index: device/hid/hid_connection_unittest.cc
diff --git a/device/hid/hid_connection_unittest.cc b/device/hid/hid_connection_unittest.cc
index a8530eeb6e1de734b9473284911f9c3bb1d4362c..fbacb52f70afff195b47b92878598ed81ffc5cf0 100644
--- a/device/hid/hid_connection_unittest.cc
+++ b/device/hid/hid_connection_unittest.cc
@@ -98,9 +98,7 @@ class HidConnectionTest : public testing::Test {
     if (!UsbTestGadget::IsTestEnabled()) return;
 
     message_loop_.reset(new base::MessageLoopForIO());
-    service_ = HidService::GetInstance(
-        message_loop_->message_loop_proxy(),
-        message_loop_->message_loop_proxy());
+    service_ = HidService::GetInstance(message_loop_->message_loop_proxy());
     ASSERT_TRUE(service_);
 
     test_gadget_ = UsbTestGadget::Claim();