Display off is done by a callback into backlight controller

powerd_unittest.cc

 // Copyright (c) 2011 The Chromium OS 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 <gtest/gtest.h>
 #include <gdk/gdk.h>
 #include <gdk/gdkx.h>
 #include <stdint.h>
 #include <X11/extensions/XTest.h>
 
@@ skipping 41 matching lines @@
 
   virtual void SetUp() {
     // Tests initialization done by the daemon's constructor.
     EXPECT_EQ(0, daemon_.battery_discharge_rate_metric_last_);
     EXPECT_EQ(0, daemon_.battery_remaining_charge_metric_last_);
     EXPECT_EQ(0, daemon_.battery_time_to_empty_metric_last_);
     EXPECT_CALL(backlight_, GetBrightness(NotNull(), NotNull()))
         .WillOnce(DoAll(SetArgumentPointee<0>(kDefaultBrightness),
                         SetArgumentPointee<1>(kMaxBrightness),
                         Return(true)));
+    EXPECT_CALL(backlight_, SetScreenOffFunc(NotNull(), NotNull()));
     prefs_.SetInt64(kPluggedBrightnessOffset, kPluggedBrightness);
     prefs_.SetInt64(kUnpluggedBrightnessOffset, kUnpluggedBrightness);
     prefs_.SetInt64(kAlsBrightnessLevel, kAlsBrightness);
     CHECK(backlight_ctl_.Init());
     ResetPowerStatus(status_);
   }
 
  protected:
   // Adds a metrics library mock expectation that the specified metric
   // will be generated.
@@ skipping 279 matching lines @@
   EXPECT_CALL(backlight_, GetBrightness(NotNull(), NotNull()))
       .WillOnce(DoAll(SetArgumentPointee<0>(kDefaultBrightness),
                       SetArgumentPointee<1>(kMaxBrightness),
                       Return(true)));
   ExpectEnumMetric("Power.BacklightLevelOnAC",
                    kDefaultBrightness, kMaxBrightness);
   daemon_.GenerateBacklightLevelMetricThunk(&daemon_);
 }
 
 }  // namespace power_manager