Add display task to trigger display configuration

ui/display/chromeos/test/test_native_display_delegate.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/display/chromeos/test/test_native_display_delegate.h"
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "ui/display/chromeos/test/action_logger.h"
 #include "ui/display/types/display_mode.h"
@@ skipping 42 matching lines @@
 }
 
 void TestNativeDisplayDelegate::ForceDPMSOn() {
   log_->AppendAction(kForceDPMS);
 }
 
 std::vector<DisplaySnapshot*> TestNativeDisplayDelegate::GetDisplays() {
   return outputs_;
 }
 
+void TestNativeDisplayDelegate::GetDisplays(
+    const GetDisplaysCallback& callback) {
+  auto result = GetDisplays();
+  if (run_async_) {
+    base::MessageLoop::current()->PostTask(FROM_HERE,
+                                           base::Bind(callback, result));
+  } else {
+    callback.Run(result);
+  }
+}
+
 void TestNativeDisplayDelegate::AddMode(const DisplaySnapshot& output,
                                         const DisplayMode* mode) {
   log_->AppendAction(GetAddOutputModeAction(output, mode));
 }
 
 bool TestNativeDisplayDelegate::Configure(const DisplaySnapshot& output,
                                           const DisplayMode* mode,
                                           const gfx::Point& origin) {
   log_->AppendAction(GetCrtcAction(output, mode, origin));
 
@@ skipping 51 matching lines @@
 
 void TestNativeDisplayDelegate::AddObserver(NativeDisplayObserver* observer) {
 }
 
 void TestNativeDisplayDelegate::RemoveObserver(
     NativeDisplayObserver* observer) {
 }
 
 }  // namespace test
 }  // namespace ui