Revert "Display mirroring persistency changes"

This reverts commit fa8dfaa.

Reason for revert:

Findit (https://goo.gl/kROfz5) identified CL at revision 524627 as the
culprit for failures in the build cycles as shown on:
https://findit-for-me.appspot.com/waterfall/culprit?key=ag9zfmZpbmRpdC1mb3ItbWVyRAsSDVdmU3VzcGVjdGVkQ0wiMWNocm9taXVtL2ZhOGRmYWE2MjFjMTcwMWRjZTg0MWY3NmVmZmVjZDA2NGZmMzc1M2UM

Sample Failed Build: https://ci.chromium.org/buildbot/chromium.chromiumos/linux-chromeos-dbg/3252

Original change's description:
> Display mirroring persistency changes
> 
> Changes:
> 1. Change mirroring persistency rule to:
> If previous mirror mode is not set (e.g. no external display in previous
> configuration), turn on mirror mode if at least one of the external
> displays was in mirror mode before and turn off mirror mode otherwise.
> If previous mirror mode is set, mirror mode remains its previous value
> as long as there are more than 1 displays.
> For example:
> Case 1: Connect display A; Turn on mirror mode; Connect display B. B
> should be in mirror mode as well.
> Case 2: Connect display A; Turn on mirror mode; Remove A; Reconnect A; A
> should be in mirror mode.
> Case 3: Connect display A; Turn on mirror mode; Remove A; Connect
> display B. B should not be in mirror mode.
> Case 4: Connect display A; Turn on mirror mode; Connect display B;
> Remove B; Remove A; Reconnect B; B should be in mirror mode.
> 
> 2. Fix a bug in MirrorWindowController: mirroring source display may be
> changed in mirror mode (e.g. Connect two external displays; Turn on
> mirror mode; Close internal display lid; Then the internal display will
> be replaced with one external display as the mirroring source.),
> reflector and mirror windows should be updated in this case.
> 
> 3. Fix broken test.
> 
> Bug: 785416,792207
> Test: MultiMirroringTest.*
> Change-Id: Ia1da9f25df2bcc04f98ab087478a14685fff7708
> Reviewed-on: https://chromium-review.googlesource.com/804647
> Commit-Queue: Weidong Guo <weidongg@chromium.org>
> Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
> Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#524627}

Change-Id: Ie18b8dc47d031984590ed98af331fdb659b17941
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 785416,792207
Reviewed-on: https://chromium-review.googlesource.com/831290
Cr-Commit-Position: refs/heads/master@{#524629}

ash/display/mirror_window_controller.cc

@@ -107,20 +107,11 @@ display::DisplayManager::MultiDisplayMode GetCurrentMultiDisplayMode() {
   display::DisplayManager* display_manager = Shell::Get()->display_manager();
   return display_manager->IsInUnifiedMode()
              ? display::DisplayManager::UNIFIED
-             : (display_manager->IsInSoftwareMirrorMode()
+             : (display_manager->IsInMirrorMode()
                     ? display::DisplayManager::MIRRORING
                     : display::DisplayManager::EXTENDED);
 }
 
-int64_t GetCurrentReflectingSourceId() {
-  display::DisplayManager* display_manager = Shell::Get()->display_manager();
-  if (display_manager->IsInUnifiedMode())
-    return display::Screen::GetScreen()->GetPrimaryDisplay().id();
-  if (display_manager->IsInSoftwareMirrorMode())
-    return display_manager->mirroring_source_id();
-  return display::kInvalidDisplayId;
-}
-
 }  // namespace
 
 struct MirrorWindowController::MirroringHostInfo {
@@ -146,26 +137,27 @@ MirrorWindowController::~MirrorWindowController() {
 
 void MirrorWindowController::UpdateWindow(
     const std::vector<display::ManagedDisplayInfo>& display_info_list) {
-  display::DisplayManager* display_manager = Shell::Get()->display_manager();
-  DCHECK(display_manager->IsInSoftwareMirrorMode() ||
-         display_manager->IsInUnifiedMode());
   static int mirror_host_count = 0;
+  display::DisplayManager* display_manager = Shell::Get()->display_manager();
+  const display::Display& primary =
+      display::Screen::GetScreen()->GetPrimaryDisplay();
+  const display::ManagedDisplayInfo& source_display_info =
+      display_manager->GetDisplayInfo(primary.id());
 
   multi_display_mode_ = GetCurrentMultiDisplayMode();
-  reflecting_source_id_ = GetCurrentReflectingSourceId();
 
   for (const display::ManagedDisplayInfo& display_info : display_info_list) {
     std::unique_ptr<RootWindowTransformer> transformer;
-    if (display_manager->IsInSoftwareMirrorMode()) {
+    if (display_manager->IsInMirrorMode()) {
       transformer.reset(CreateRootWindowTransformerForMirroredDisplay(
-          display_manager->GetDisplayInfo(reflecting_source_id_),
-          display_info));
-    } else {
-      DCHECK(display_manager->IsInUnifiedMode());
+          source_display_info, display_info));
+    } else if (display_manager->IsInUnifiedMode()) {
       display::Display display =
           display_manager->GetMirroringDisplayById(display_info.id());
       transformer.reset(CreateRootWindowTransformerForUnifiedDesktop(
-          display::Screen::GetScreen()->GetPrimaryDisplay().bounds(), display));
+          primary.bounds(), display));
+    } else {
+      NOTREACHED();
     }
 
     if (mirroring_host_info_map_.find(display_info.id()) ==
@@ -205,7 +197,7 @@ void MirrorWindowController::UpdateWindow(
         AshWindowTreeHost* unified_ash_host =
             Shell::Get()
                 ->window_tree_host_manager()
-                ->GetAshWindowTreeHostForDisplayId(reflecting_source_id_);
+                ->GetAshWindowTreeHostForDisplayId(primary.id());
         unified_ash_host->RegisterMirroringHost(host_info->ash_host.get());
         aura::client::SetScreenPositionClient(host->window(),
                                               screen_position_client_.get());
@@ -232,9 +224,7 @@ void MirrorWindowController::UpdateWindow(
               aura::Env::GetInstance()
                   ->context_factory_private()
                   ->CreateReflector(
-                      Shell::GetRootWindowForDisplayId(reflecting_source_id_)
-                          ->GetHost()
-                          ->compositor(),
+                      Shell::GetPrimaryRootWindow()->GetHost()->compositor(),
                       mirror_window->layer());
         }
       }
@@ -288,10 +278,9 @@ void MirrorWindowController::UpdateWindow() {
 void MirrorWindowController::CloseIfNotNecessary() {
   display::DisplayManager::MultiDisplayMode new_mode =
       GetCurrentMultiDisplayMode();
-  int64_t new_reflecting_source_id = GetCurrentReflectingSourceId();
-  if (multi_display_mode_ != new_mode ||
-      reflecting_source_id_ != new_reflecting_source_id) {
+  if (multi_display_mode_ != new_mode) {
     Close(true);
+    multi_display_mode_ = new_mode;
   } else {
     UpdateWindow();
   }

ash/display/mirror_window_controller.h

@@ -104,9 +104,6 @@ class ASH_EXPORT MirrorWindowController
 
   display::DisplayManager::MultiDisplayMode multi_display_mode_;
 
-  // The id of the display being mirrored in the reflector.
-  int64_t reflecting_source_id_ = display::kInvalidDisplayId;
-
   std::unique_ptr<aura::client::ScreenPositionClient> screen_position_client_;
 
   std::unique_ptr<ui::Reflector> reflector_;

ash/display/mirror_window_controller_unittest.cc

@@ -66,9 +66,8 @@ TEST_F(MirrorWindowControllerTest, MirrorCursorBasic) {
   aura::test::TestWindowDelegate test_window_delegate;
   test_window_delegate.set_window_component(HTTOP);
 
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
   UpdateDisplay("400x400,400x400");
-  display_manager()->SetMirrorMode(true);
-  RunAllPendingInMessageLoop();
   aura::Window* root = Shell::Get()->GetPrimaryRootWindow();
   std::unique_ptr<aura::Window> window(aura::test::CreateTestWindowWithDelegate(
       &test_window_delegate, 0, gfx::Rect(50, 50, 100, 100), root));
@@ -119,9 +118,8 @@ TEST_F(MirrorWindowControllerTest, MirrorCursorRotate) {
   aura::test::TestWindowDelegate test_window_delegate;
   test_window_delegate.set_window_component(HTTOP);
 
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
   UpdateDisplay("400x400,400x400");
-  display_manager()->SetMirrorMode(true);
-  RunAllPendingInMessageLoop();
   aura::Window* root = Shell::Get()->GetPrimaryRootWindow();
   std::unique_ptr<aura::Window> window(aura::test::CreateTestWindowWithDelegate(
       &test_window_delegate, 0, gfx::Rect(50, 50, 100, 100), root));
@@ -177,11 +175,10 @@ TEST_F(MirrorWindowControllerTest, MirrorCursorLocations) {
     return;
 
   MirrorWindowTestApi test_api;
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
 
   // Test with device scale factor.
   UpdateDisplay("400x600*2,400x600");
-  display_manager()->SetMirrorMode(true);
-  RunAllPendingInMessageLoop();
 
   aura::Window* root = Shell::Get()->GetPrimaryRootWindow();
   ui::test::EventGenerator generator(root);
@@ -239,9 +236,8 @@ TEST_F(MirrorWindowControllerTest, MirrorCursorMoveOnEnter) {
   EXPECT_EQ(display::Display::ROTATE_0,
             cursor_test_api.GetCurrentCursorRotation());
 
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
   UpdateDisplay("400x400*2/r,400x400");
-  display_manager()->SetMirrorMode(true);
-  RunAllPendingInMessageLoop();
 
   // Entering mirror mode should have centered the cursor on the primary display
   // because the cursor's previous position is out of bounds.
@@ -275,6 +271,8 @@ TEST_F(MirrorWindowControllerTest, DockMode) {
       CreateDisplayInfo(external_id, gfx::Rect(1, 1, 100, 100));
   std::vector<display::ManagedDisplayInfo> display_info_list;
 
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
+
   // software mirroring.
   display_info_list.push_back(internal_display_info);
   display_info_list.push_back(external_display_info);
@@ -284,16 +282,15 @@ TEST_F(MirrorWindowControllerTest, DockMode) {
           .SetFirstDisplayAsInternalDisplay();
   EXPECT_EQ(internal_id, internal_display_id);
 
-  display_manager()->SetMirrorMode(true);
-  RunAllPendingInMessageLoop();
   EXPECT_EQ(1U, display_manager()->GetNumDisplays());
-  EXPECT_TRUE(display_manager()->IsInSoftwareMirrorMode());
+  EXPECT_TRUE(display_manager()->IsInMirrorMode());
   EXPECT_EQ(external_id,
             display_manager()->GetMirroringDestinationDisplayIdList()[0]);
 
   // dock mode.
   display_info_list.clear();
   display_info_list.push_back(external_display_info);
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
   display_manager()->OnNativeDisplaysChanged(display_info_list);
   EXPECT_EQ(1U, display_manager()->GetNumDisplays());
   EXPECT_FALSE(display_manager()->IsInMirrorMode());
@@ -302,6 +299,7 @@ TEST_F(MirrorWindowControllerTest, DockMode) {
   display_info_list.clear();
   display_info_list.push_back(internal_display_info);
   display_info_list.push_back(external_display_info);
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
   display_manager()->OnNativeDisplaysChanged(display_info_list);
   EXPECT_EQ(1U, display_manager()->GetNumDisplays());
   EXPECT_TRUE(display_manager()->IsInMirrorMode());

ash/display/root_window_transformers_unittest.cc

@@ -405,8 +405,8 @@ TEST_F(RootWindowTransformersTest, ConvertHostToRootCoords) {
 
 TEST_F(RootWindowTransformersTest, LetterBoxPillarBox) {
   MirrorWindowTestApi test_api;
+  display_manager()->SetMultiDisplayMode(display::DisplayManager::MIRRORING);
   UpdateDisplay("400x200,500x500");
-  display_manager()->SetMirrorMode(true);
   std::unique_ptr<RootWindowTransformer> transformer(
       CreateCurrentRootWindowTransformerForMirroring());
   // Y margin must be margin is (500 - 500/400 * 200) / 2 = 125.