Fix potential GPU crash caused by VT switching

ui/display/chromeos/display_configurator_unittest.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/display_configurator.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/macros.h"
@@ skipping 1722 matching lines @@
       log_->GetActionsAndClear());
 }
 
 TEST_F(DisplayConfiguratorTest, ExternalControl) {
   InitWithSingleOutput();
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_SINGLE);
   configurator_.RelinquishControl(
       base::Bind(&DisplayConfiguratorTest::OnDisplayControlUpdated,
                  base::Unretained(this)));
   EXPECT_EQ(CALLBACK_SUCCESS, PopDisplayControlResult());
-  EXPECT_EQ(JoinActions(kRelinquishDisplayControl, nullptr),
-            log_->GetActionsAndClear());
+  EXPECT_EQ(
+      JoinActions(
+          kGrab,
+          GetFramebufferAction(small_mode_.size(), outputs_[0].get(), nullptr)
+              .c_str(),
+          GetCrtcAction(*outputs_[0], nullptr, gfx::Point(0, 0)).c_str(),
+          kUngrab, kRelinquishDisplayControl, nullptr),
+      log_->GetActionsAndClear());
   configurator_.TakeControl(
       base::Bind(&DisplayConfiguratorTest::OnDisplayControlUpdated,
                  base::Unretained(this)));
   EXPECT_EQ(CALLBACK_SUCCESS, PopDisplayControlResult());
   EXPECT_EQ(
       JoinActions(
           kTakeDisplayControl, kGrab,
           GetFramebufferAction(small_mode_.size(), outputs_[0].get(), nullptr)
               .c_str(),
           GetCrtcAction(*outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
-          kUngrab, nullptr),
+          kForceDPMS, kUngrab, nullptr),
       log_->GetActionsAndClear());
 }
 
 TEST_F(DisplayConfiguratorTest,
        SetDisplayPowerWhilePendingConfigurationTaskRunning) {
   // Start out with two displays in extended mode.
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED);
   Init(false);
   configurator_.ForceInitialConfigure(0);
   log_->GetActionsAndClear();
@@ skipping 401 matching lines @@
   configurator_.ResumeDisplays();
   EXPECT_EQ(kLongDelay, config_waiter_.Wait());
   EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_ON,
             configurator_.current_power_state());
   EXPECT_EQ(MULTIPLE_DISPLAY_STATE_MULTI_EXTENDED,
             configurator_.display_state());
 }
 
 }  // namespace test
 }  // namespace ui