Don't update framebuffer_size to 0x0 when the framebuffer size didn't change.

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 "base/memory/scoped_vector.h"
 #include "base/message_loop/message_loop.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/display/chromeos/test/action_logger_util.h"
@@ skipping 367 matching lines @@
           GetCrtcAction(outputs_[1],
                         &big_mode_,
                         gfx::Point(0,
                                    small_mode_.size().height() +
                                        DisplayConfigurator::kVerticalGap))
               .c_str(),
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
   EXPECT_FALSE(mirroring_controller_.SoftwareMirroringEnabled());
+  const gfx::Size framebuffer_size = configurator_.framebuffer_size();
+  DCHECK(!framebuffer_size.IsEmpty());
 
   observer_.Reset();
   configurator_.SetDisplayMode(MULTIPLE_DISPLAY_STATE_DUAL_MIRROR);
   EXPECT_EQ(JoinActions(kGrab, kUngrab, NULL), log_->GetActionsAndClear());
   EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED,
             configurator_.display_state());
   EXPECT_TRUE(mirroring_controller_.SoftwareMirroringEnabled());
+  EXPECT_EQ(framebuffer_size.ToString(),
+            configurator_.framebuffer_size().ToString());
+
   EXPECT_EQ(1, observer_.num_changes());
 
   // Setting MULTIPLE_DISPLAY_STATE_DUAL_MIRROR should try to reconfigure.
   observer_.Reset();
   configurator_.SetDisplayMode(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED);
   EXPECT_EQ(JoinActions(NULL), log_->GetActionsAndClear());
   EXPECT_FALSE(mirroring_controller_.SoftwareMirroringEnabled());
   EXPECT_EQ(1, observer_.num_changes());
 
   // Set back to software mirror mode.
@@ skipping 220 matching lines @@
   EXPECT_TRUE(mirroring_controller_.SoftwareMirroringEnabled());
   EXPECT_EQ(1, observer_.num_changes());
 }
 
 TEST_F(DisplayConfiguratorTest, SuspendAndResume) {
   InitWithSingleOutput();
 
   // No preparation is needed before suspending when the display is already
   // on.  The configurator should still reprobe on resume in case a display
   // was connected while suspended.
+  const gfx::Size framebuffer_size = configurator_.framebuffer_size();
+  DCHECK(!framebuffer_size.IsEmpty());
   configurator_.SuspendDisplays();
+  EXPECT_EQ(framebuffer_size.ToString(),
+            configurator_.framebuffer_size().ToString());
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
   configurator_.ResumeDisplays();
   EXPECT_TRUE(test_api_.TriggerConfigureTimeout());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
@@ skipping 126 matching lines @@
 
   UpdateOutputs(1, true);
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(big_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], &big_mode_, gfx::Point(0, 0)).c_str(),
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
+  const gfx::Size framebuffer_size = configurator_.framebuffer_size();
+  DCHECK(!framebuffer_size.IsEmpty());
+
+  UpdateOutputs(0, true);
+  EXPECT_EQ(JoinActions(kGrab, kUngrab, NULL), log_->GetActionsAndClear());
+  EXPECT_EQ(framebuffer_size.ToString(),
+            configurator_.framebuffer_size().ToString());
 }
 
 TEST_F(DisplayConfiguratorTest, StartWithTwoOutputs) {
   UpdateOutputs(2, false);
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
   configurator_.Init(false);
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
 
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_MIRROR);
   configurator_.ForceInitialConfigure(0);
@@ skipping 550 matching lines @@
                         GetFramebufferAction(small_mode_.size(), &outputs_[0],
                                              nullptr).c_str(),
                         GetCrtcAction(outputs_[0], &small_mode_,
                                       gfx::Point(0, 0)).c_str(),
                         kUngrab, NULL),
             log_->GetActionsAndClear());
 }
 
 }  // namespace test
 }  // namespace ui